Bug 1713627 - Remove code obsoleted by the replacing the Text Encoding menu with one item. r=jaws,emk

Differential Revision: https://phabricator.services.mozilla.com/D116391
2021-06-21 08:09:43 +00:00 · 2021-06-21 08:09:43 +00:00 · abbbf94915
--- a/Cargo.lock
+++ b/Cargo.lock
@ -2025,7 +2025,6 @@ dependencies = [
 "rusqlite",
 "rust_minidump_writer_linux",
 "rustc_version",
- "shift_or_euc_c",
 "static_prefs",
 "storage",
 "unic-langid",
@ -4632,26 +4631,6 @@ dependencies = [
 "opaque-debug",
 ]

-[[package]]
-name = "shift_or_euc"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f930dea4685b9803954b9d74cdc175c6d946a22f2eafe5aa2e9a58cdcae7da8c"
-dependencies = [
- "encoding_rs",
- "memchr",
-]
-
-[[package]]
-name = "shift_or_euc_c"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c81ec08c8a68c45c48d8ef58b80ce038cc9945891c4a4996761e2ec5cba05abc"
-dependencies = [
- "encoding_rs",
- "shift_or_euc",
-]
-
 [[package]]
 name = "shlex"
 version = "0.1.1"
--- a/browser/actors/BrowserTabChild.jsm
+++ b/browser/actors/BrowserTabChild.jsm
@ -98,9 +98,8 @@ class BrowserTabChild extends JSWindowActorChild {
        } catch (e) {}
        break;

-      case "UpdateCharacterSet":
-        docShell.charset = message.data.value;
-        docShell.gatherCharsetMenuTelemetry();
+      case "ForceEncodingDetection":
+        docShell.forceEncodingDetection();
        break;
    }
  }
--- a/browser/base/content/appmenu-viewcache.inc.xhtml
+++ b/browser/base/content/appmenu-viewcache.inc.xhtml
@ -547,16 +547,6 @@
    </vbox>
  </panelview>

-  <panelview id="PanelUI-characterEncodingView" flex="1">
-    <vbox class="panel-subview-body">
-      <vbox id="PanelUI-characterEncodingView-pinned"
-            class="PanelUI-characterEncodingView-list"/>
-      <toolbarseparator/>
-      <vbox id="PanelUI-characterEncodingView-charsets"
-            class="PanelUI-characterEncodingView-list"/>
-    </vbox>
-  </panelview>
-
  <panelview id="PanelUI-panicView" flex="1"
             descriptionheightworkaround="true">
    <vbox class="panel-subview-body">
@ -595,11 +585,6 @@
                     class="subviewbutton subviewbutton-iconic"
                     data-l10n-id="appmenu-taskmanager"
                     oncommand="switchToTabHavingURI('about:performance', true)"/>
-      <toolbarbutton id="appMenu-characterencoding-button"
-                     class="subviewbutton subviewbutton-nav"
-                     label="&charsetMenu2.label;"
-                     closemenu="none"
-                     oncommand="PanelUI.showSubView('PanelUI-characterEncodingView', this)"/>
      <toolbarbutton id="appMenu-workoffline-button"
                     class="subviewbutton"
                     data-l10n-id="more-menu-go-offline"
--- a/browser/base/content/browser-doctype.inc
+++ b/browser/base/content/browser-doctype.inc
@ -2,8 +2,6 @@
 %brandDTD;
 <!ENTITY % browserDTD SYSTEM "chrome://browser/locale/browser.dtd" >
 %browserDTD;
-<!ENTITY % charsetDTD SYSTEM "chrome://global/locale/charsetMenu.dtd" >
-%charsetDTD;
 <!ENTITY % textcontextDTD SYSTEM "chrome://global/locale/textcontext.dtd" >
 %textcontextDTD;
 <!ENTITY % placesDTD SYSTEM "chrome://browser/locale/places/places.dtd">
--- a/browser/base/content/browser-menubar.inc
+++ b/browser/base/content/browser-menubar.inc
@ -143,8 +143,7 @@
            </menu>

            <menu id="view-menu" data-l10n-id="menu-view">
-              <menupopup id="menu_viewPopup"
-                         onpopupshowing="updateCharacterEncodingMenuState();">
+              <menupopup id="menu_viewPopup">
                <menu id="viewToolbarsMenu" data-l10n-id="menu-view-toolbars-menu">
                  <menupopup id="view-menu-popup" onpopupshowing="onViewToolbarsPopupShowing(event);">
                    <menuseparator/>
@ -203,7 +202,7 @@
                </menu>
                <menuitem id="repair-text-encoding"
                          disabled="true"
-                          oncommand="BrowserSetForcedCharacterSet('_autodetect_all')"
+                          oncommand="BrowserForceEncodingDetection();"
                          data-l10n-id="menu-view-repair-text-encoding"/>
                <menuseparator/>
 #ifdef XP_MACOSX
--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@ -27,7 +27,6 @@ XPCOMUtils.defineLazyModuleGetters(this, {
  BrowserUtils: "resource://gre/modules/BrowserUtils.jsm",
  BrowserWindowTracker: "resource:///modules/BrowserWindowTracker.jsm",
  CFRPageActions: "resource://activity-stream/lib/CFRPageActions.jsm",
-  CharsetMenu: "resource://gre/modules/CharsetMenu.jsm",
  Color: "resource://gre/modules/Color.jsm",
  ContextualIdentityService:
    "resource://gre/modules/ContextualIdentityService.jsm",
@ -4884,24 +4883,6 @@ function updateUserContextUIIndicator() {
  hbox.hidden = false;
 }

-/**
- * Makes the Character Encoding menu enabled or disabled as appropriate.
- * To be called when the View menu or the app menu is opened.
- */
-function updateCharacterEncodingMenuState() {
-  let charsetMenu = document.getElementById("charsetMenu");
-  // gBrowser is null on Mac when the menubar shows in the context of
-  // non-browser windows. The above elements may be null depending on
-  // what parts of the menubar are present. E.g. no app menu on Mac.
-  if (gBrowser && gBrowser.selectedBrowser.mayEnableCharacterEncodingMenu) {
-    if (charsetMenu) {
-      charsetMenu.removeAttribute("disabled");
-    }
-  } else if (charsetMenu) {
-    charsetMenu.setAttribute("disabled", "true");
-  }
-}
-
 var XULBrowserWindow = {
  // Stored Status, Link and Loading values
  status: "",
@ -7078,37 +7059,11 @@ function handleDroppedLink(
  }
 }

-function BrowserSetForcedCharacterSet(aCharset) {
-  if (aCharset) {
-    if (aCharset == "Japanese") {
-      aCharset = "Shift_JIS";
-    }
-    gBrowser.selectedBrowser.characterSet = aCharset;
-    // Save the forced character-set
-    PlacesUIUtils.setCharsetForPage(
-      gBrowser.currentURI,
-      aCharset,
-      window
-    ).catch(Cu.reportError);
-  }
-  BrowserCharsetReload();
-}
-
-function BrowserCharsetReload() {
+function BrowserForceEncodingDetection() {
+  gBrowser.selectedBrowser.forceEncodingDetection();
  BrowserReloadWithFlags(Ci.nsIWebNavigation.LOAD_FLAGS_CHARSET_CHANGE);
 }

-function UpdateCurrentCharset(target) {
-  let selectedCharset = CharsetMenu.foldCharset(
-    gBrowser.selectedBrowser.characterSet,
-    gBrowser.selectedBrowser.charsetAutodetected
-  );
-  for (let menuItem of target.getElementsByTagName("menuitem")) {
-    let isSelected = menuItem.getAttribute("charset") === selectedCharset;
-    menuItem.setAttribute("checked", isSelected);
-  }
-}
-
 var ToolbarContextMenu = {
  updateDownloadsAutoHide(popup) {
    let checkbox = document.getElementById(
--- a/browser/components/customizableui/CustomizableWidgets.jsm
+++ b/browser/components/customizableui/CustomizableWidgets.jsm
@ -439,7 +439,7 @@ const CustomizableWidgets = [
    id: "characterencoding-button",
    l10nId: "repair-text-encoding-button",
    onCommand(aEvent) {
-      aEvent.view.BrowserSetForcedCharacterSet("_autodetect_all");
+      aEvent.view.BrowserForceEncodingDetection();
    },
  },
  {
--- a/docshell/base/nsDocShell.cpp
+++ b/docshell/base/nsDocShell.cpp
@ -370,7 +370,6 @@ nsDocShell::nsDocShell(BrowsingContext* aBrowsingContext,
    : nsDocLoader(true),
      mContentWindowID(aContentWindowID),
      mBrowsingContext(aBrowsingContext),
-      mForcedCharset(nullptr),
      mParentCharset(nullptr),
      mTreeOwner(nullptr),
      mScrollbarPref(ScrollbarPreference::Auto),
@ -1527,7 +1526,7 @@ nsDocShell::GetCharset(nsACString& aCharset) {
 }

 NS_IMETHODIMP
-nsDocShell::GatherCharsetMenuTelemetry() {
+nsDocShell::ForceEncodingDetection() {
  nsCOMPtr<nsIContentViewer> viewer;
  GetContentViewer(getter_AddRefs(viewer));
  if (!viewer) {
@ -1539,15 +1538,11 @@ nsDocShell::GatherCharsetMenuTelemetry() {
    return NS_OK;
  }

-  if (mForcedAutodetection) {
-    LOGCHARSETMENU(("ENCODING_OVERRIDE_USED_AUTOMATIC"));
-    Telemetry::ScalarSet(Telemetry::ScalarID::ENCODING_OVERRIDE_USED_AUTOMATIC,
-                         true);
-  } else {
-    LOGCHARSETMENU(("ENCODING_OVERRIDE_USED_MANUAL"));
-    Telemetry::ScalarSet(Telemetry::ScalarID::ENCODING_OVERRIDE_USED_MANUAL,
-                         true);
-  }
+  mForcedAutodetection = true;
+
+  LOGCHARSETMENU(("ENCODING_OVERRIDE_USED_AUTOMATIC"));
+  Telemetry::ScalarSet(Telemetry::ScalarID::ENCODING_OVERRIDE_USED_AUTOMATIC,
+                       true);

  nsIURI* url = doc->GetOriginalURI();
  bool isFileURL = url && SchemeIsFile(url);
@ -1561,28 +1556,6 @@ nsDocShell::GatherCharsetMenuTelemetry() {
      Telemetry::AccumulateCategorical(
          Telemetry::LABELS_ENCODING_OVERRIDE_SITUATION_2::AutoOverridden);
      break;
-    case kCharsetFromUserForced:
-    case kCharsetFromUserForcedJapaneseAutoDetection:
-      LOGCHARSETMENU(("ManuallyOverridden"));
-      Telemetry::AccumulateCategorical(
-          Telemetry::LABELS_ENCODING_OVERRIDE_SITUATION_2::ManuallyOverridden);
-      break;
-    case kCharsetFromTopLevelDomain:
-      if (encoding == WINDOWS_1252_ENCODING) {
-        LOGCHARSETMENU(("UnlabeledInLk"));
-        Telemetry::AccumulateCategorical(
-            Telemetry::LABELS_ENCODING_OVERRIDE_SITUATION_2::UnlabeledInLk);
-      } else {
-        LOGCHARSETMENU(("UnlabeledJp"));
-        Telemetry::AccumulateCategorical(
-            Telemetry::LABELS_ENCODING_OVERRIDE_SITUATION_2::UnlabeledJp);
-      }
-      break;
-    case kCharsetFromFinalJapaneseAutoDetection:
-      LOGCHARSETMENU(("UnlabeledJp"));
-      Telemetry::AccumulateCategorical(
-          Telemetry::LABELS_ENCODING_OVERRIDE_SITUATION_2::UnlabeledJp);
-      break;
    case kCharsetFromInitialAutoDetectionASCII:
      // Deliberately no final version
      LOGCHARSETMENU(("UnlabeledAscii"));
@ -1657,31 +1630,6 @@ nsDocShell::GatherCharsetMenuTelemetry() {
  return NS_OK;
 }

-NS_IMETHODIMP
-nsDocShell::SetCharset(const nsACString& aCharset) {
-  mForcedAutodetection = false;
-  if (aCharset.IsEmpty()) {
-    mForcedCharset = nullptr;
-    return NS_OK;
-  }
-  if (aCharset.EqualsLiteral("_autodetect_all")) {
-    mForcedCharset = WINDOWS_1252_ENCODING;
-    mForcedAutodetection = true;
-    return NS_OK;
-  }
-  const Encoding* encoding = Encoding::ForLabel(aCharset);
-  if (!encoding) {
-    // Reject unknown labels
-    return NS_ERROR_INVALID_ARG;
-  }
-  if (!encoding->IsAsciiCompatible() && encoding != ISO_2022_JP_ENCODING) {
-    // Reject XSS hazards
-    return NS_ERROR_INVALID_ARG;
-  }
-  mForcedCharset = encoding;
-  return NS_OK;
-}
-
 void nsDocShell::SetParentCharset(const Encoding*& aCharset,
                                  int32_t aCharsetSource,
                                  nsIPrincipal* aPrincipal) {
@ -2042,30 +1990,6 @@ nsDocShell::GetMayEnableCharacterEncodingMenu(
  return NS_OK;
 }

-NS_IMETHODIMP
-nsDocShell::GetCharsetAutodetected(bool* aCharsetAutodetected) {
-  *aCharsetAutodetected = false;
-  if (!mContentViewer) {
-    return NS_OK;
-  }
-  Document* doc = mContentViewer->GetDocument();
-  if (!doc) {
-    return NS_OK;
-  }
-  int32_t source = doc->GetDocumentCharacterSetSource();
-
-  if ((source >= kCharsetFromInitialAutoDetectionASCII &&
-       source <= kCharsetFromFinalAutoDetectionFile) ||
-      source == kCharsetFromUserForcedJapaneseAutoDetection ||
-      source == kCharsetFromPendingUserForcedAutoDetection ||
-      source == kCharsetFromInitialUserForcedAutoDetection ||
-      source == kCharsetFromFinalUserForcedAutoDetection) {
-    *aCharsetAutodetected = true;
-  }
-
-  return NS_OK;
-}
-
 NS_IMETHODIMP
 nsDocShell::GetAllDocShellsInSubtree(int32_t aItemType,
                                     DocShellEnumeratorDirection aDirection,
--- a/docshell/base/nsDocShell.h
+++ b/docshell/base/nsDocShell.h
@ -327,10 +327,10 @@ class nsDocShell final : public nsDocLoader,
  void SetInFrameSwap(bool aInSwap) { mInFrameSwap = aInSwap; }
  bool InFrameSwap();

-  const mozilla::Encoding* GetForcedCharset() { return mForcedCharset; }
-
  bool GetForcedAutodetection() { return mForcedAutodetection; }

+  void ResetForcedAutodetection() { mForcedAutodetection = false; }
+
  mozilla::HTMLEditor* GetHTMLEditorInternal();
  nsresult SetHTMLEditorInternal(mozilla::HTMLEditor* aHTMLEditor);

@ -1189,7 +1189,6 @@ class nsDocShell final : public nsDocLoader,

  mozilla::UniquePtr<mozilla::gfx::Matrix5x4> mColorMatrix;

-  const mozilla::Encoding* mForcedCharset;
  const mozilla::Encoding* mParentCharset;

  // WEAK REFERENCES BELOW HERE.
--- a/docshell/base/nsIDocShell.idl
+++ b/docshell/base/nsIDocShell.idl
@ -494,17 +494,10 @@ interface nsIDocShell : nsIDocShellTreeItem
  /**
   * Upon getting, returns the canonical encoding label of the document
   * currently loaded into this docshell.
-   *
-   * Upon setting, sets the forced encoding for compatibility with legacy callers.
   */
-  attribute ACString charset;
+  readonly attribute ACString charset;

-  /**
-   * Called when the user chose an encoding override from the character
-   * encoding menu. Separate from the setter for the charset property to avoid
-   * extensions adding noise to the data.
-   */
-  void gatherCharsetMenuTelemetry();
+  void forceEncodingDetection();

  /**
   * In a child docshell, this is the charset of the parent docshell
@ -620,11 +613,6 @@ interface nsIDocShell : nsIDocShellTreeItem
   */
  [infallible] readonly attribute boolean mayEnableCharacterEncodingMenu;

-  /**
-   * Indicates that the character encoding was autodetected.
-   */
-  [infallible] readonly attribute boolean charsetAutodetected;
-
           attribute  nsIEditor editor;
  readonly attribute  boolean   editable;             /* this docShell is editable */
  readonly attribute  boolean   hasEditingSession;    /* this docShell has an editing session */
--- a/docshell/test/browser/browser.ini
+++ b/docshell/test/browser/browser.ini
@ -21,9 +21,6 @@ support-files =
  file_bug234628-6-child.html
  file_bug234628-6-child.html^headers^
  file_bug234628-6.html
-  file_bug234628-7-child.html
-  file_bug234628-7-child.html^headers^
-  file_bug234628-7.html
  file_bug234628-8-child.html
  file_bug234628-8.html
  file_bug234628-9-child.html
@ -43,14 +40,8 @@ support-files =
  file_bug1328501.html
  file_bug1328501_frame.html
  file_bug1328501_framescript.js
-  file_bug1543077-1-child.html
-  file_bug1543077-1.html
-  file_bug1543077-2-child.html
-  file_bug1543077-2.html
  file_bug1543077-3-child.html
  file_bug1543077-3.html
-  file_bug1543077-4-child.html
-  file_bug1543077-4.html
  file_multiple_pushState.html
  file_onbeforeunload_0.html
  file_onbeforeunload_1.html
@ -85,10 +76,7 @@ skip-if =
  os == "linux" && bits == 64 && !debug # Bug 1607713
  fission && os == "mac" && debug  # Bug 1713903 - new Fission platform triage
 [browser_backforward_userinteraction_about.js]
-[browser_bug1543077-1.js]
-[browser_bug1543077-2.js]
 [browser_bug1543077-3.js]
-[browser_bug1543077-4.js]
 [browser_bug1594938.js]
 [browser_bug1206879.js]
 [browser_bug1309900_crossProcessHistoryNavigation.js]
@ -118,7 +106,6 @@ skip-if = !fission || !crashreporter # On a crash we only keep history when fiss
 [browser_bug234628-4.js]
 [browser_bug234628-5.js]
 [browser_bug234628-6.js]
-[browser_bug234628-7.js]
 [browser_bug234628-8.js]
 [browser_bug234628-9.js]
 [browser_bug349769.js]
--- a/docshell/test/browser/browser_bug134911.js
+++ b/docshell/test/browser/browser_bug134911.js
@ -29,7 +29,7 @@ function afterOpen() {
    content.document.getElementById("testinput").value = TEXT.enteredText2;
  }).then(() => {
    /* Force the page encoding to Shift_JIS */
-    BrowserSetForcedCharacterSet("Shift_JIS");
+    BrowserForceEncodingDetection();
  });
 }

--- a/docshell/test/browser/browser_bug1543077-1.js
+++ b/docshell/test/browser/browser_bug1543077-1.js
@ -1,47 +0,0 @@
-function test() {
-  var rootDir = "http://mochi.test:8888/browser/docshell/test/browser/";
-  runCharsetTest(
-    rootDir + "file_bug1543077-1.html",
-    afterOpen,
-    "Japanese",
-    afterChangeCharset
-  );
-}
-
-function afterOpen() {
-  is(
-    content.document.documentElement.textContent.indexOf("\u0434"),
-    131,
-    "Parent doc should be IBM866 initially"
-  );
-
-  is(
-    content.frames[0].document.documentElement.textContent.indexOf("\u0434"),
-    87,
-    "Child doc should be IBM866 initially"
-  );
-}
-
-function afterChangeCharset() {
-  is(
-    content.document.documentElement.textContent.indexOf("\u3042"),
-    131,
-    "Parent doc should decode as EUC-JP subsequently"
-  );
-  is(
-    content.frames[0].document.documentElement.textContent.indexOf("\u3042"),
-    87,
-    "Child doc should decode as EUC-JP subsequently"
-  );
-
-  is(
-    content.document.characterSet,
-    "EUC-JP",
-    "Parent doc should report EUC-JP subsequently"
-  );
-  is(
-    content.frames[0].document.characterSet,
-    "EUC-JP",
-    "Child doc should report EUC-JP subsequently"
-  );
-}
--- a/docshell/test/browser/browser_bug1543077-2.js
+++ b/docshell/test/browser/browser_bug1543077-2.js
@ -1,47 +0,0 @@
-function test() {
-  var rootDir = "http://mochi.test:8888/browser/docshell/test/browser/";
-  runCharsetTest(
-    rootDir + "file_bug1543077-2.html",
-    afterOpen,
-    "Japanese",
-    afterChangeCharset
-  );
-}
-
-function afterOpen() {
-  is(
-    content.document.documentElement.textContent.indexOf("\u0412"),
-    134,
-    "Parent doc should be IBM866 initially"
-  );
-
-  is(
-    content.frames[0].document.documentElement.textContent.indexOf("\u0412"),
-    90,
-    "Child doc should be IBM866 initially"
-  );
-}
-
-function afterChangeCharset() {
-  is(
-    content.document.documentElement.textContent.indexOf("\u3042"),
-    134,
-    "Parent doc should decode as Shift_JIS subsequently"
-  );
-  is(
-    content.frames[0].document.documentElement.textContent.indexOf("\u3042"),
-    90,
-    "Child doc should decode as Shift_JIS subsequently"
-  );
-
-  is(
-    content.document.characterSet,
-    "Shift_JIS",
-    "Parent doc should report Shift_JIS subsequently"
-  );
-  is(
-    content.frames[0].document.characterSet,
-    "Shift_JIS",
-    "Child doc should report Shift_JIS subsequently"
-  );
-}
--- a/docshell/test/browser/browser_bug1543077-3.js
+++ b/docshell/test/browser/browser_bug1543077-3.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug1543077-3.html",
    afterOpen,
-    "Japanese",
    afterChangeCharset
  );
 }
--- a/docshell/test/browser/browser_bug1543077-4.js
+++ b/docshell/test/browser/browser_bug1543077-4.js
@ -1,47 +0,0 @@
-function test() {
-  var rootDir = "http://mochi.test:8888/browser/docshell/test/browser/";
-  runCharsetTest(
-    rootDir + "file_bug1543077-4.html",
-    afterOpen,
-    "Japanese",
-    afterChangeCharset
-  );
-}
-
-function afterOpen() {
-  is(
-    content.document.documentElement.textContent.indexOf("\u0434"),
-    131,
-    "Parent doc should be IBM866 initially"
-  );
-
-  is(
-    content.frames[0].document.documentElement.textContent.indexOf("\u0412"),
-    90,
-    "Child doc should be IBM866 initially"
-  );
-}
-
-function afterChangeCharset() {
-  is(
-    content.document.documentElement.textContent.indexOf("\u3042"),
-    131,
-    "Parent doc should decode as EUC-JP subsequently"
-  );
-  is(
-    content.frames[0].document.documentElement.textContent.indexOf("\u3042"),
-    90,
-    "Child doc should decode as Shift_JIS subsequently"
-  );
-
-  is(
-    content.document.characterSet,
-    "EUC-JP",
-    "Parent doc should report EUC-JP subsequently"
-  );
-  is(
-    content.frames[0].document.characterSet,
-    "Shift_JIS",
-    "Child doc should report Shift_JIS subsequently"
-  );
-}
--- a/docshell/test/browser/browser_bug1648464-1.js
+++ b/docshell/test/browser/browser_bug1648464-1.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug1648464-1.html",
    afterOpen,
-    "_autodetect_all",
    afterChangeCharset
  );
 }
--- a/docshell/test/browser/browser_bug1688368-1.js
+++ b/docshell/test/browser/browser_bug1688368-1.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug1688368-1.sjs",
    afterOpen,
-    "UTF-8",
    afterChangeCharset
  );
 }
--- a/docshell/test/browser/browser_bug234628-1.js
+++ b/docshell/test/browser/browser_bug234628-1.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug234628-1.html",
    afterOpen,
-    "windows-1251",
    afterChangeCharset
  );
 }
@ -24,24 +23,25 @@ function afterOpen() {

 function afterChangeCharset() {
  is(
-    content.document.documentElement.textContent.indexOf("\u0402"),
+    content.document.documentElement.textContent.indexOf("\u20AC"),
    129,
-    "Parent doc should decode as windows-1251 subsequently"
+    "Parent doc should be windows-1252 subsequently"
  );
+
  is(
-    content.frames[0].document.documentElement.textContent.indexOf("\u0402"),
+    content.frames[0].document.documentElement.textContent.indexOf("\u20AC"),
    85,
-    "Child doc should decode as windows-1251 subsequently"
+    "Child doc should be windows-1252 subsequently"
  );

  is(
    content.document.characterSet,
-    "windows-1251",
-    "Parent doc should report windows-1251 subsequently"
+    "windows-1252",
+    "Parent doc should report windows-1252 subsequently"
  );
  is(
    content.frames[0].document.characterSet,
-    "windows-1251",
-    "Child doc should report windows-1251 subsequently"
+    "windows-1252",
+    "Child doc should report windows-1252 subsequently"
  );
 }
--- a/docshell/test/browser/browser_bug234628-10.js
+++ b/docshell/test/browser/browser_bug234628-10.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug234628-10.html",
    afterOpen,
-    "windows-1251",
    afterChangeCharset
  );
 }
@ -24,9 +23,9 @@ function afterOpen() {

 function afterChangeCharset() {
  is(
-    content.document.documentElement.textContent.indexOf("\u0402"),
+    content.document.documentElement.textContent.indexOf("\u20AC"),
    151,
-    "Parent doc should decode as windows-1251 subsequently"
+    "Parent doc should be windows-1252 initially"
  );
  is(
    content.frames[0].document.documentElement.textContent.indexOf("\u20AC"),
@ -36,8 +35,8 @@ function afterChangeCharset() {

  is(
    content.document.characterSet,
-    "windows-1251",
-    "Parent doc should report windows-1251 subsequently"
+    "windows-1252",
+    "Parent doc should report windows-1252 subsequently"
  );
  is(
    content.frames[0].document.characterSet,
--- a/docshell/test/browser/browser_bug234628-11.js
+++ b/docshell/test/browser/browser_bug234628-11.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug234628-11.html",
    afterOpen,
-    "windows-1251",
    afterChangeCharset
  );
 }
@ -24,9 +23,9 @@ function afterOpen() {

 function afterChangeCharset() {
  is(
-    content.document.documentElement.textContent.indexOf("\u0402"),
+    content.document.documentElement.textContent.indexOf("\u20AC"),
    193,
-    "Parent doc should decode as windows-1251 subsequently"
+    "Parent doc should be windows-1252 subsequently"
  );
  is(
    content.frames[0].document.documentElement.textContent.indexOf("\u20AC"),
@ -36,8 +35,8 @@ function afterChangeCharset() {

  is(
    content.document.characterSet,
-    "windows-1251",
-    "Parent doc should report windows-1251 subsequently"
+    "windows-1252",
+    "Parent doc should report windows-1252 subsequently"
  );
  is(
    content.frames[0].document.characterSet,
--- a/docshell/test/browser/browser_bug234628-2.js
+++ b/docshell/test/browser/browser_bug234628-2.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug234628-2.html",
    afterOpen,
-    "windows-1251",
    afterChangeCharset
  );
 }
@ -26,26 +25,25 @@ function afterOpen() {

 function afterChangeCharset() {
  is(
-    content.document.documentElement.textContent.indexOf("\u0402"),
+    content.document.documentElement.textContent.indexOf("\u20AC"),
    129,
-    "Parent doc should decode as windows-1251 subsequently"
+    "Parent doc should be windows-1252 subsequently"
  );
+
  is(
-    content.frames[0].document.documentElement.textContent.indexOf(
-      "\u0432\u201A\u00AC"
-    ),
+    content.frames[0].document.documentElement.textContent.indexOf("\u20AC"),
    78,
-    "Child doc should decode as windows-1251 subsequently"
+    "Child doc should be UTF-8 subsequently"
  );

  is(
    content.document.characterSet,
-    "windows-1251",
-    "Parent doc should report windows-1251 subsequently"
+    "windows-1252",
+    "Parent doc should report windows-1252 subsequently"
  );
  is(
    content.frames[0].document.characterSet,
-    "windows-1251",
-    "Child doc should report windows-1251 subsequently"
+    "UTF-8",
+    "Child doc should report UTF-8 subsequently"
  );
 }
--- a/docshell/test/browser/browser_bug234628-3.js
+++ b/docshell/test/browser/browser_bug234628-3.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug234628-3.html",
    afterOpen,
-    "windows-1251",
    afterChangeCharset
  );
 }
@ -24,26 +23,25 @@ function afterOpen() {

 function afterChangeCharset() {
  is(
-    content.document.documentElement.textContent.indexOf("\u0402"),
+    content.document.documentElement.textContent.indexOf("\u20AC"),
    118,
-    "Parent doc should decode as windows-1251 subsequently"
+    "Parent doc should be windows-1252 subsequently"
  );
+
  is(
-    content.frames[0].document.documentElement.textContent.indexOf(
-      "\u0432\u201A\u00AC"
-    ),
+    content.frames[0].document.documentElement.textContent.indexOf("\u20AC"),
    73,
-    "Child doc should decode as windows-1251 subsequently"
+    "Child doc should be utf-8 subsequently"
  );

  is(
    content.document.characterSet,
-    "windows-1251",
-    "Parent doc should report windows-1251 subsequently"
+    "windows-1252",
+    "Parent doc should report windows-1252 subsequently"
  );
  is(
    content.frames[0].document.characterSet,
-    "windows-1251",
-    "Child doc should report windows-1251 subsequently"
+    "UTF-8",
+    "Child doc should report UTF-8 subsequently"
  );
 }
--- a/docshell/test/browser/browser_bug234628-4.js
+++ b/docshell/test/browser/browser_bug234628-4.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug234628-4.html",
    afterOpen,
-    "windows-1251",
    afterChangeCharset
  );
 }
@ -24,9 +23,9 @@ function afterOpen() {

 function afterChangeCharset() {
  is(
-    content.document.documentElement.textContent.indexOf("\u0402"),
+    content.document.documentElement.textContent.indexOf("\u20AC"),
    132,
-    "Parent doc should decode as windows-1251 subsequently"
+    "Parent doc should decode as windows-1252 subsequently"
  );
  is(
    content.frames[0].document.documentElement.textContent.indexOf("\u20AC"),
@ -36,8 +35,8 @@ function afterChangeCharset() {

  is(
    content.document.characterSet,
-    "windows-1251",
-    "Parent doc should report windows-1251 subsequently"
+    "windows-1252",
+    "Parent doc should report windows-1252 subsequently"
  );
  is(
    content.frames[0].document.characterSet,
--- a/docshell/test/browser/browser_bug234628-5.js
+++ b/docshell/test/browser/browser_bug234628-5.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug234628-5.html",
    afterOpen,
-    "windows-1251",
    afterChangeCharset
  );
 }
@ -24,9 +23,9 @@ function afterOpen() {

 function afterChangeCharset() {
  is(
-    content.document.documentElement.textContent.indexOf("\u0402"),
+    content.document.documentElement.textContent.indexOf("\u20AC"),
    146,
-    "Parent doc should decode as windows-1251 subsequently"
+    "Parent doc should be windows-1252 subsequently"
  );
  is(
    content.frames[0].document.documentElement.textContent.indexOf("\u20AC"),
@ -36,8 +35,8 @@ function afterChangeCharset() {

  is(
    content.document.characterSet,
-    "windows-1251",
-    "Parent doc should report windows-1251 subsequently"
+    "windows-1252",
+    "Parent doc should report windows-1252 subsequently"
  );
  is(
    content.frames[0].document.characterSet,
--- a/docshell/test/browser/browser_bug234628-6.js
+++ b/docshell/test/browser/browser_bug234628-6.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug234628-6.html",
    afterOpen,
-    "windows-1251",
    afterChangeCharset
  );
 }
@ -24,20 +23,21 @@ function afterOpen() {

 function afterChangeCharset() {
  is(
-    content.document.documentElement.textContent.indexOf("\u0402"),
+    content.document.documentElement.textContent.indexOf("\u20AC"),
    190,
-    "Parent doc should decode as windows-1251 subsequently"
+    "Parent doc should be windows-1252 subsequently"
  );
+
  is(
    content.frames[0].document.documentElement.textContent.indexOf("\u20AC"),
    109,
-    "Child doc should decode as utf-16 subsequently"
+    "Child doc should be utf-16 subsequently"
  );

  is(
    content.document.characterSet,
-    "windows-1251",
-    "Parent doc should report windows-1251 subsequently"
+    "windows-1252",
+    "Parent doc should report windows-1252 subsequently"
  );
  is(
    content.frames[0].document.characterSet,
--- a/docshell/test/browser/browser_bug234628-7.js
+++ b/docshell/test/browser/browser_bug234628-7.js
@ -1,49 +0,0 @@
-function test() {
-  var rootDir = "http://mochi.test:8888/browser/docshell/test/browser/";
-  runCharsetTest(
-    rootDir + "file_bug234628-7.html",
-    afterOpen,
-    "windows-1251",
-    afterChangeCharset
-  );
-}
-
-function afterOpen() {
-  is(
-    content.document.documentElement.textContent.indexOf("\u20AC"),
-    188,
-    "Parent doc should be windows-1252 initially"
-  );
-
-  is(
-    content.frames[0].document.documentElement.textContent.indexOf("\u20AC"),
-    107,
-    "Child doc should be utf-8 initially"
-  );
-}
-
-function afterChangeCharset() {
-  is(
-    content.document.documentElement.textContent.indexOf("\u0402"),
-    188,
-    "Parent doc should decode as windows-1251 subsequently"
-  );
-  is(
-    content.frames[0].document.documentElement.textContent.indexOf(
-      "\u0432\u201A\u00AC"
-    ),
-    107,
-    "Child doc should decode as windows-1251 subsequently"
-  );
-
-  is(
-    content.document.characterSet,
-    "windows-1251",
-    "Parent doc should report windows-1251 subsequently"
-  );
-  is(
-    content.frames[0].document.characterSet,
-    "windows-1251",
-    "Child doc should report windows-1251 subsequently"
-  );
-}
--- a/docshell/test/browser/browser_bug234628-8.js
+++ b/docshell/test/browser/browser_bug234628-8.js
@ -1,6 +1,6 @@
 function test() {
  var rootDir = "http://mochi.test:8888/browser/docshell/test/browser/";
-  runCharsetTest(rootDir + "file_bug234628-8.html", afterOpen);
+  runCharsetCheck(rootDir + "file_bug234628-8.html", afterOpen);
 }

 function afterOpen() {
--- a/docshell/test/browser/browser_bug234628-9.js
+++ b/docshell/test/browser/browser_bug234628-9.js
@ -1,6 +1,6 @@
 function test() {
  var rootDir = "http://mochi.test:8888/browser/docshell/test/browser/";
-  runCharsetTest(rootDir + "file_bug234628-9.html", afterOpen);
+  runCharsetCheck(rootDir + "file_bug234628-9.html", afterOpen);
 }

 function afterOpen() {
--- a/docshell/test/browser/browser_bug673087-2.js
+++ b/docshell/test/browser/browser_bug673087-2.js
@ -3,7 +3,6 @@ function test() {
  runCharsetTest(
    rootDir + "file_bug673087-2.html",
    afterOpen,
-    "windows-1252",
    afterChangeCharset
  );
 }
--- a/docshell/test/browser/browser_bug92473.js
+++ b/docshell/test/browser/browser_bug92473.js
@ -34,7 +34,7 @@ function afterOpen() {

  /* Test that the content on load is the expected wrong decoding */
  testContent(wrongText).then(() => {
-    BrowserSetForcedCharacterSet("Shift_JIS");
+    BrowserForceEncodingDetection();
  });
 }

--- a/docshell/test/browser/file_bug1543077-1-child.html
+++ b/docshell/test/browser/file_bug1543077-1-child.html
@ -1,11 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-<meta content="width=device-width, initial-scale=1" name="viewport">
-<title>No encoding declaration in parent or child</title>
-</head>
-<body>
-<p>Hiragana letter a if decoded as EUC-JP: ¤¢</p>
-</body>
-</html>
-
--- a/docshell/test/browser/file_bug1543077-1.html
+++ b/docshell/test/browser/file_bug1543077-1.html
@ -1,16 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-<meta content="width=device-width, initial-scale=1" name="viewport">
-<title>No encoding declaration in parent or child</title>
-</head>
-<body>
-<h1>No encoding declaration in parent or child</h1>
-
-<p>Hiragana letter a if decoded as EUC-JP: ¤¢</p>
-
-<iframe src="file_bug1543077-1-child.html"></iframe>
-
-</body>
-</html>
-
--- a/docshell/test/browser/file_bug1543077-2-child.html
+++ b/docshell/test/browser/file_bug1543077-2-child.html
@ -1,11 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-<meta content="width=device-width, initial-scale=1" name="viewport">
-<title>No encoding declaration in parent or child</title>
-</head>
-<body>
-<p>Hiragana letter a if decoded as Shift_JIS: ‚ </p>
-</body>
-</html>
-
--- a/docshell/test/browser/file_bug1543077-2.html
+++ b/docshell/test/browser/file_bug1543077-2.html
@ -1,16 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-<meta content="width=device-width, initial-scale=1" name="viewport">
-<title>No encoding declaration in parent or child</title>
-</head>
-<body>
-<h1>No encoding declaration in parent or child</h1>
-
-<p>Hiragana letter a if decoded as Shift_JIS: ‚ </p>
-
-<iframe src="file_bug1543077-2-child.html"></iframe>
-
-</body>
-</html>
-
--- a/docshell/test/browser/file_bug1543077-4-child.html
+++ b/docshell/test/browser/file_bug1543077-4-child.html
@ -1,11 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-<meta content="width=device-width, initial-scale=1" name="viewport">
-<title>No encoding declaration in parent or child</title>
-</head>
-<body>
-<p>Hiragana letter a if decoded as Shift_JIS: ‚ </p>
-</body>
-</html>
-
--- a/docshell/test/browser/file_bug1543077-4.html
+++ b/docshell/test/browser/file_bug1543077-4.html
@ -1,16 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-<meta content="width=device-width, initial-scale=1" name="viewport">
-<title>No encoding declaration in parent or child</title>
-</head>
-<body>
-<h1>No encoding declaration in parent or child</h1>
-
-<p>Hiragana letter a if decoded as EUC-JP: ¤¢</p>
-
-<iframe src="file_bug1543077-4-child.html"></iframe>
-
-</body>
-</html>
-
--- a/docshell/test/browser/file_bug234628-7-child.html
+++ b/docshell/test/browser/file_bug234628-7-child.html
@ -1,12 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-<meta content="width=device-width, initial-scale=1" name="viewport">
-<title>meta declaration in parent and BOMless UTF-8 with HTTP charset in child</title>
-</head>
-<body>
-<p>Euro sign if decoded as UTF-8: €</p>
-<p>a with diaeresis if decoded as UTF-8: ä</p>
-</body>
-</html>
-
--- a/docshell/test/browser/file_bug234628-7-child.html^headers^
+++ b/docshell/test/browser/file_bug234628-7-child.html^headers^
@ -1 +0,0 @@
-Content-Type: text/html; charset=utf-8
--- a/docshell/test/browser/file_bug234628-7.html
+++ b/docshell/test/browser/file_bug234628-7.html
@ -1,18 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-<meta charset="windows-1252">
-<meta content="width=device-width, initial-scale=1" name="viewport">
-<title>meta declaration in parent and BOMless UTF-8 with HTTP charset in child</title>
-</head>
-<body>
-<h1>meta declaration in parent and BOMless UTF-8 with HTTP charset in child</h1>
-
-<p>Euro sign if decoded as Windows-1252: €</p>
-<p>a with diaeresis if decoded as Windows-1252: ä</p>
-
-<iframe src="file_bug234628-7-child.html"></iframe>
-
-</body>
-</html>
-
--- a/docshell/test/browser/head.js
+++ b/docshell/test/browser/head.js
@ -63,34 +63,22 @@ function timelineTestOpenUrl(url) {
 }

 /**
- * Helper function for charset tests. It loads |url| in a new tab,
- * runs |check1| in a ContentTask when the page is ready, switches the
- * charset to |charset|, and then runs |check2| in a ContentTask when
- * the page has finished reloading.
- *
- * |charset| and |check2| can be omitted, in which case the test
- * finishes when |check1| completes.
+ * Helper function for encoding override tests, loads URL, runs check1,
+ * forces encoding detection, runs check2.
 */
-function runCharsetTest(url, check1, charset, check2) {
+function runCharsetTest(url, check1, check2) {
  waitForExplicitFinish();

  BrowserTestUtils.openNewForegroundTab(gBrowser, url, true).then(afterOpen);

  function afterOpen() {
-    if (charset) {
-      BrowserTestUtils.browserLoaded(gBrowser.selectedBrowser).then(
-        afterChangeCharset
-      );
+    BrowserTestUtils.browserLoaded(gBrowser.selectedBrowser).then(
+      afterChangeCharset
+    );

-      SpecialPowers.spawn(gBrowser.selectedBrowser, [], check1).then(() => {
-        BrowserSetForcedCharacterSet(charset);
-      });
-    } else {
-      SpecialPowers.spawn(gBrowser.selectedBrowser, [], check1).then(() => {
-        gBrowser.removeCurrentTab();
-        finish();
-      });
-    }
+    SpecialPowers.spawn(gBrowser.selectedBrowser, [], check1).then(() => {
+      BrowserForceEncodingDetection();
+    });
  }

  function afterChangeCharset() {
@ -101,6 +89,23 @@ function runCharsetTest(url, check1, charset, check2) {
  }
 }

+/**
+ * Helper function for charset tests. It loads |url| in a new tab,
+ * runs |check|.
+ */
+function runCharsetCheck(url, check) {
+  waitForExplicitFinish();
+
+  BrowserTestUtils.openNewForegroundTab(gBrowser, url, true).then(afterOpen);
+
+  function afterOpen() {
+    SpecialPowers.spawn(gBrowser.selectedBrowser, [], check).then(() => {
+      gBrowser.removeCurrentTab();
+      finish();
+    });
+  }
+}
+
 async function pushState(url, frameId) {
  info(
    `Doing a pushState, expecting to load ${url} ${
--- a/dom/base/nsDOMWindowUtils.cpp
+++ b/dom/base/nsDOMWindowUtils.cpp
@ -362,8 +362,11 @@ nsDOMWindowUtils::GetDocCharsetIsForced(bool* aIsForced) {
  *aIsForced = false;

  Document* doc = GetDocument();
-  *aIsForced =
-      doc && doc->GetDocumentCharacterSetSource() >= kCharsetFromUserForced;
+  if (doc) {
+    auto source = doc->GetDocumentCharacterSetSource();
+    *aIsForced = source == kCharsetFromInitialUserForcedAutoDetection ||
+                 source == kCharsetFromFinalUserForcedAutoDetection;
+  }
  return NS_OK;
 }

--- a/dom/html/nsHTMLDocument.cpp
+++ b/dom/html/nsHTMLDocument.cpp
@ -206,7 +206,7 @@ void nsHTMLDocument::TryUserForcedCharset(nsIContentViewer* aCv,
                                          nsIDocShell* aDocShell,
                                          int32_t& aCharsetSource,
                                          NotNull<const Encoding*>& aEncoding) {
-  if (kCharsetFromUserForced <= aCharsetSource) {
+  if (aCharsetSource >= kCharsetFromXmlDeclarationUtf16) {
    return;
  }

@ -215,20 +215,11 @@ void nsHTMLDocument::TryUserForcedCharset(nsIContentViewer* aCv,
    return;
  }

-  if (aDocShell) {
+  if (aDocShell && nsDocShell::Cast(aDocShell)->GetForcedAutodetection()) {
    // This is the Character Encoding menu code path in Firefox
-    auto encoding = nsDocShell::Cast(aDocShell)->GetForcedCharset();
-
-    if (encoding) {
-      if (!IsAsciiCompatible(encoding)) {
-        return;
-      }
-      aEncoding = WrapNotNull(encoding);
-      aCharsetSource = nsDocShell::Cast(aDocShell)->GetForcedAutodetection()
-                           ? kCharsetFromPendingUserForcedAutoDetection
-                           : kCharsetFromUserForced;
-      aDocShell->SetCharset(""_ns);
-    }
+    aEncoding = WINDOWS_1252_ENCODING;
+    aCharsetSource = kCharsetFromPendingUserForcedAutoDetection;
+    nsDocShell::Cast(aDocShell)->ResetForcedAutodetection();
  }
 }

@ -238,7 +229,7 @@ void nsHTMLDocument::TryParentCharset(nsIDocShell* aDocShell,
  if (!aDocShell) {
    return;
  }
-  if (aCharsetSource >= kCharsetFromUserForced) {
+  if (aCharsetSource >= kCharsetFromXmlDeclarationUtf16) {
    return;
  }

@ -250,9 +241,7 @@ void nsHTMLDocument::TryParentCharset(nsIDocShell* aDocShell,
  if (!parentCharset) {
    return;
  }
-  if (kCharsetFromUserForced == parentSource ||
-      kCharsetFromUserForcedJapaneseAutoDetection == parentSource ||
-      kCharsetFromPendingUserForcedAutoDetection == parentSource ||
+  if (kCharsetFromPendingUserForcedAutoDetection == parentSource ||
      kCharsetFromInitialUserForcedAutoDetection == parentSource ||
      kCharsetFromFinalUserForcedAutoDetection == parentSource) {
    if (WillIgnoreCharsetOverride() ||
@ -261,11 +250,7 @@ void nsHTMLDocument::TryParentCharset(nsIDocShell* aDocShell,
      return;
    }
    aEncoding = WrapNotNull(parentCharset);
-    aCharsetSource =
-        (kCharsetFromUserForced == parentSource ||
-         kCharsetFromUserForcedJapaneseAutoDetection == parentSource)
-            ? kCharsetFromUserForced
-            : kCharsetFromPendingUserForcedAutoDetection;
+    aCharsetSource = kCharsetFromPendingUserForcedAutoDetection;
    return;
  }

@ -693,11 +678,9 @@ bool nsHTMLDocument::WillIgnoreCharsetOverride() {
  switch (mCharacterSetSource) {
    case kCharsetUninitialized:
    case kCharsetFromFallback:
-    case kCharsetFromTopLevelDomain:
    case kCharsetFromDocTypeDefault:
    case kCharsetFromInitialAutoDetectionWouldHaveBeenUTF8:
    case kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8DependedOnTLD:
-    case kCharsetFromFinalJapaneseAutoDetection:
    case kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8:
    case kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8DependedOnTLD:
    case kCharsetFromParentFrame:
@ -705,8 +688,6 @@ bool nsHTMLDocument::WillIgnoreCharsetOverride() {
    case kCharsetFromMetaPrescan:
    case kCharsetFromMetaTag:
    case kCharsetFromChannel:
-    case kCharsetFromUserForced:
-    case kCharsetFromUserForcedJapaneseAutoDetection:
      return false;
  }

--- a/dom/html/nsHTMLDocument.h
+++ b/dom/html/nsHTMLDocument.h
@ -176,9 +176,6 @@ class nsHTMLDocument : public mozilla::dom::Document {
  void TryUserForcedCharset(nsIContentViewer* aCv, nsIDocShell* aDocShell,
                            int32_t& aCharsetSource,
                            NotNull<const Encoding*>& aEncoding);
-  static void TryCacheCharset(nsICachingChannel* aCachingChannel,
-                              int32_t& aCharsetSource,
-                              NotNull<const Encoding*>& aEncoding);
  void TryParentCharset(nsIDocShell* aDocShell, int32_t& charsetSource,
                        NotNull<const Encoding*>& aEncoding);

--- a/dom/interfaces/base/nsIBrowser.idl
+++ b/dom/interfaces/base/nsIBrowser.idl
@ -67,12 +67,6 @@ interface nsIBrowser : nsISupports
   */
  attribute boolean mayEnableCharacterEncodingMenu;

-  /**
-   * Whether or not the character encoding was detected by analyzing
-   * content (as opposed to reading a protocol label).
-   */
-  attribute boolean charsetAutodetected;
-
  /**
   * Called by Gecko to update the browser when its state changes.
   *
@ -102,8 +96,6 @@ interface nsIBrowser : nsISupports
   * @param aCharset the character set of the document
   * @param aMayEnableCharacterEncodingMenu whether or not the content encoding
   *                                        menu may be enabled
-   * @param aCharsetAutodetected whether or not the given character set was
-   *                             autodetected
   * @param aDocumentURI the URI of the new document
   * @param aTitle the title of the new doucment
   * @param aContentPrincipal the security principal of the new document
@ -120,7 +112,6 @@ interface nsIBrowser : nsISupports
  void updateForLocationChange(in nsIURI aLocation,
                               in AString aCharset,
                               in boolean aMayEnableCharacterEncodingMenu,
-                               in boolean aCharsetAutodetected,
                               in nsIURI aDocumentURI,
                               in AString aTitle,
                               in nsIPrincipal aContentPrincipal,
--- a/dom/ipc/BrowserChild.cpp
+++ b/dom/ipc/BrowserChild.cpp
@ -3602,7 +3602,6 @@ NS_IMETHODIMP BrowserChild::OnStateChange(nsIWebProgress* aWebProgress,
    stateChangeData->isNavigating() = docShell->GetIsNavigating();
    stateChangeData->mayEnableCharacterEncodingMenu() =
        docShell->GetMayEnableCharacterEncodingMenu();
-    stateChangeData->charsetAutodetected() = docShell->GetCharsetAutodetected();

    RefPtr<Document> document = browsingContext->GetExtantDocument();
    if (document && aStateFlags & nsIWebProgressListener::STATE_STOP) {
@ -3701,8 +3700,6 @@ NS_IMETHODIMP BrowserChild::OnLocationChange(nsIWebProgress* aWebProgress,

    locationChangeData->mayEnableCharacterEncodingMenu() =
        docShell->GetMayEnableCharacterEncodingMenu();
-    locationChangeData->charsetAutodetected() =
-        docShell->GetCharsetAutodetected();

    locationChangeData->contentPrincipal() = document->NodePrincipal();
    locationChangeData->contentPartitionedPrincipal() =
--- a/dom/ipc/BrowserParent.cpp
+++ b/dom/ipc/BrowserParent.cpp
@ -2713,8 +2713,6 @@ mozilla::ipc::IPCResult BrowserParent::RecvOnStateChange(
      Unused << browser->SetIsNavigating(aStateChangeData->isNavigating());
      Unused << browser->SetMayEnableCharacterEncodingMenu(
          aStateChangeData->mayEnableCharacterEncodingMenu());
-      Unused << browser->SetCharsetAutodetected(
-          aStateChangeData->charsetAutodetected());
      Unused << browser->UpdateForStateChange(aStateChangeData->charset(),
                                              aStateChangeData->documentURI(),
                                              aStateChangeData->contentType());
@ -2783,7 +2781,6 @@ mozilla::ipc::IPCResult BrowserParent::RecvOnLocationChange(
      Unused << browser->UpdateForLocationChange(
          aLocation, aLocationChangeData->charset(),
          aLocationChangeData->mayEnableCharacterEncodingMenu(),
-          aLocationChangeData->charsetAutodetected(),
          aLocationChangeData->documentURI(), aLocationChangeData->title(),
          aLocationChangeData->contentPrincipal(),
          aLocationChangeData->contentPartitionedPrincipal(),
--- a/dom/ipc/PBrowser.ipdl
+++ b/dom/ipc/PBrowser.ipdl
@ -130,7 +130,6 @@ struct WebProgressStateChangeData
 {
  bool isNavigating;
  bool mayEnableCharacterEncodingMenu;
-  bool charsetAutodetected;

  // The following fields are only set when the aStateFlags param passed with
  // this struct is |nsIWebProgress.STATE_STOP|.
@ -144,7 +143,6 @@ struct WebProgressLocationChangeData
  bool isNavigating;
  bool isSyntheticDocument;
  bool mayEnableCharacterEncodingMenu;
-  bool charsetAutodetected;
  nsString contentType;
  nsString title;
  nsString charset;
--- a/intl/JapaneseDetector.h
+++ b/intl/JapaneseDetector.h
@ -1,124 +0,0 @@
-// Copyright 2018 Mozilla Foundation. See the COPYRIGHT
-// file at the top-level directory of this distribution.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-// Mostly copied and pasted from
-// third_party/rust/shift_or_euc/src/lib.rs , so
-// "top-level directory of this distribution" above refers to
-// third_party/rust/shift_or_euc/
-
-#ifndef mozilla_JapaneseDetector_h
-#define mozilla_JapaneseDetector_h
-
-#include "mozilla/Encoding.h"
-
-namespace mozilla {
-class JapaneseDetector;
-};  // namespace mozilla
-
-#define SHIFT_OR_EUC_DETECTOR mozilla::JapaneseDetector
-
-#include "shift_or_euc.h"
-
-namespace mozilla {
-
-/**
- * A Japanese legacy encoding detector for detecting between Shift_JIS,
- * EUC-JP, and, optionally, ISO-2022-JP _given_ the assumption that the
- * encoding is one of those.
- *
- * # Principle of Operation
- *
- * The detector is based on two observations:
- *
- * 1. The ISO-2022-JP escape sequences don't normally occur in Shift_JIS or
- * EUC-JP, so encountering such an escape sequence (before non-ASCII has been
- * encountered) can be taken as indication of ISO-2022-JP.
- * 2. When normal (full-with) kana or common kanji encoded as Shift_JIS is
- * decoded as EUC-JP, or vice versa, the result is either an error or
- * half-width katakana, and it's very uncommon for Japanese HTML to have
- * half-width katakana character before a normal kana or common kanji
- * character. Therefore, if decoding as Shift_JIS results in error or
- * have-width katakana, the detector decides that the content is EUC-JP, and
- * vice versa.
- *
- * # Failure Modes
- *
- * The detector gives the wrong answer if the text has a half-width katakana
- * character before normal kana or common kanji. Some uncommon kanji are
- * undecidable. (All JIS X 0208 Level 1 kanji are decidable.)
- *
- * The half-width katakana issue is mainly relevant for old 8-bit JIS X
- * 0201-only text files that would decode correctly as Shift_JIS but that the
- * detector detects as EUC-JP.
- *
- * The undecidable kanji issue does not realistically show up when a full
- * document is fed to the detector, because, realistically, in a full
- * document, there is at least one kana or common kanji. It can occur,
- * though, if the detector is only run on a prefix of a document and the
- * prefix only contains the title of the document. It is possible for
- * document title to consist entirely of undecidable kanji. (Indeed,
- * Japanese Wikipedia has articles with such titles.) If the detector is
- * undecided, a fallback to Shift_JIS should be used.
- */
-class JapaneseDetector final {
- public:
-  ~JapaneseDetector() {}
-
-  static void operator delete(void* aDetector) {
-    shift_or_euc_detector_free(reinterpret_cast<JapaneseDetector*>(aDetector));
-  }
-
-  /**
-   * Instantiates the detector. If `aAllow2022` is `true` the possible
-   * guesses are Shift_JIS, EUC-JP, ISO-2022-JP, and undecided. If
-   * `aAllow2022` is `false`, the possible guesses are Shift_JIS, EUC-JP,
-   * and undecided.
-   */
-  static inline UniquePtr<JapaneseDetector> Create(bool aAllow2022) {
-    UniquePtr<JapaneseDetector> detector(shift_or_euc_detector_new(aAllow2022));
-    return detector;
-  }
-
-  /**
-   * Feeds bytes to the detector. If `aLast` is `true` the end of the stream
-   * is considered to occur immediately after the end of `aBuffer`.
-   * Otherwise, the stream is expected to continue. `aBuffer` may be empty.
-   *
-   * If you're running the detector only on a prefix of a complete
-   * document, _do not_ pass `aLast` as `true` after the prefix if the
-   * stream as a whole still contains more content.
-   *
-   * Returns `SHIFT_JIS_ENCODING` if the detector guessed
-   * Shift_JIS. Returns `EUC_JP_ENCODING` if the detector
-   * guessed EUC-JP. Returns `ISO_2022_JP_ENCODING` if the
-   * detector guessed ISO-2022-JP (only possible if `true` was passed as
-   * `aAllow2022` when instantiating the detector). Returns `nullptr` if the
-   * detector is undecided. If `nullptr` is returned even when passing `true`
-   * as `aLast`, falling back to Shift_JIS is the best guess for Web
-   * purposes.
-   *
-   * Do not call again after the method has returned non-`nullptr` or after
-   * the method has been called with `true` as `aLast`. (Asserts if the
-   * previous sentence isn't adhered to.)
-   */
-  inline const mozilla::Encoding* Feed(Span<const uint8_t> aBuffer,
-                                       bool aLast) {
-    return shift_or_euc_detector_feed(this, aBuffer.Elements(),
-                                      aBuffer.Length(), aLast);
-  }
-
- private:
-  JapaneseDetector() = delete;
-  JapaneseDetector(const JapaneseDetector&) = delete;
-  JapaneseDetector& operator=(const JapaneseDetector&) = delete;
-};
-
-};  // namespace mozilla
-
-#endif  // mozilla_JapaneseDetector_h
--- a/intl/moz.build
+++ b/intl/moz.build
@ -27,14 +27,12 @@ DIRS += [
 EXPORTS.mozilla += [
    "Encoding.h",
    "EncodingDetector.h",
-    "JapaneseDetector.h",
 ]

 EXPORTS += [
    "../third_party/rust/chardetng_c/include/chardetng.h",
    "../third_party/rust/encoding_c/include/encoding_rs.h",
    "../third_party/rust/encoding_c/include/encoding_rs_statics.h",
-    "../third_party/rust/shift_or_euc_c/include/shift_or_euc.h",
 ]


--- a/mobile/android/locales/l10n.toml
+++ b/mobile/android/locales/l10n.toml
@ -177,10 +177,6 @@ exclude-multi-locale = [
    reference = "toolkit/locales/en-US/toolkit/about/*Compat.ftl"
    l10n = "{l}toolkit/toolkit/about/*Compat.ftl"

-[[paths]]
-    reference = "toolkit/locales/en-US/chrome/global/charsetMenu.properties"
-    l10n = "{l}toolkit/chrome/global/charsetMenu.properties"
-
 [[paths]]
    reference = "toolkit/locales/en-US/chrome/global/commonDialogs.properties"
    l10n = "{l}toolkit/chrome/global/commonDialogs.properties"
--- a/modules/libpref/init/StaticPrefList.yaml
+++ b/modules/libpref/init/StaticPrefList.yaml
@ -5581,24 +5581,6 @@
 # Prefs starting with "intl."
 #---------------------------------------------------------------------------

-# Whether the new encoding detector is enabled for the .jp TLD.
- name: intl.charset.detector.ng.jp.enabled
-  type: bool
-  value: true
-  mirror: always
-
-# Whether the new encoding detector is enabled for the .in TLD.
- name: intl.charset.detector.ng.in.enabled
-  type: bool
-  value: true
-  mirror: always
-
-# Whether the new encoding detector is enabled for the .lk TLD.
- name: intl.charset.detector.ng.lk.enabled
-  type: bool
-  value: true
-  mirror: always
-
 # If true, dispatch the keydown and keyup events on any web apps even during
 # composition.
 - name: intl.ime.hack.on_any_apps.fire_key_events_for_composition
--- a/parser/html/nsHtml5StreamParser.cpp
+++ b/parser/html/nsHtml5StreamParser.cpp
@ -20,7 +20,6 @@
 #include "mozilla/DebugOnly.h"
 #include "mozilla/Encoding.h"
 #include "mozilla/EncodingDetector.h"
-#include "mozilla/JapaneseDetector.h"
 #include "mozilla/Likely.h"
 #include "mozilla/Maybe.h"
 #include "mozilla/SchedulerGroup.h"
@ -307,9 +306,6 @@ int32_t nsHtml5StreamParser::MaybeRollBackSource(int32_t aSource) {
 }

 void nsHtml5StreamParser::GuessEncoding(bool aEof, bool aInitial) {
-  if (mJapaneseDetector) {
-    return;
-  }
  if (aInitial) {
    if (!mDetectorHasSeenNonAscii) {
      mDetectorHadOnlySeenAsciiWhenFirstGuessing = true;
@ -320,7 +316,6 @@ void nsHtml5StreamParser::GuessEncoding(bool aEof, bool aInitial) {
  bool forced = (mCharsetSource == kCharsetFromPendingUserForcedAutoDetection ||
                 mCharsetSource == kCharsetFromInitialUserForcedAutoDetection);
  MOZ_ASSERT(
-      mCharsetSource != kCharsetFromFinalJapaneseAutoDetection &&
      mCharsetSource != kCharsetFromFinalUserForcedAutoDetection &&
      mCharsetSource != kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8 &&
      mCharsetSource !=
@ -385,8 +380,7 @@ void nsHtml5StreamParser::GuessEncoding(bool aEof, bool aInitial) {
      mCharsetSource = MaybeRollBackSource(source);
      mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource);
    } else {
-      MOZ_ASSERT(mCharsetSource < kCharsetFromFinalJapaneseAutoDetection ||
-                 forced);
+      MOZ_ASSERT(mCharsetSource < kCharsetFromXmlDeclarationUtf16 || forced);
      // We've already committed to a decoder. Request a reload from the
      // docshell.
      mTreeBuilder->NeedsCharsetSwitchTo(encoding, source, 0);
@ -407,44 +401,9 @@ void nsHtml5StreamParser::GuessEncoding(bool aEof, bool aInitial) {
  }
 }

-void nsHtml5StreamParser::FeedJapaneseDetector(Span<const uint8_t> aBuffer,
-                                               bool aLast) {
-  MOZ_ASSERT(!mDecodingLocalFileWithoutTokenizing);
-  const Encoding* detected = mJapaneseDetector->Feed(aBuffer, aLast);
-  if (!detected) {
-    return;
-  }
-  DontGuessEncoding();
-  int32_t source = kCharsetFromFinalJapaneseAutoDetection;
-  if (mCharsetSource == kCharsetFromUserForced) {
-    source = kCharsetFromUserForcedJapaneseAutoDetection;
-  }
-  if (detected == mEncoding) {
-    MOZ_ASSERT(mCharsetSource < source, "Why are we running chardet at all?");
-    mCharsetSource = source;
-    mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource);
-  } else if (HasDecoder()) {
-    // We've already committed to a decoder. Request a reload from the
-    // docshell.
-    mTreeBuilder->NeedsCharsetSwitchTo(WrapNotNull(detected), source, 0);
-    FlushTreeOpsAndDisarmTimer();
-    Interrupt();
-  } else {
-    // Got a confident answer from the sniffing buffer. That code will
-    // take care of setting up the decoder.
-    mEncoding = WrapNotNull(detected);
-    mCharsetSource = source;
-    mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource);
-  }
-}
-
 void nsHtml5StreamParser::FeedDetector(Span<const uint8_t> aBuffer,
                                       bool aLast) {
-  if (mJapaneseDetector) {
-    FeedJapaneseDetector(aBuffer, aLast);
-  } else {
-    mDetectorHasSeenNonAscii = mDetector->Feed(aBuffer, aLast);
-  }
+  mDetectorHasSeenNonAscii = mDetector->Feed(aBuffer, aLast);
 }

 void nsHtml5StreamParser::SetViewSourceTitle(nsIURI* aURL) {
@ -491,13 +450,12 @@ nsHtml5StreamParser::SetupDecodingAndWriteSniffingBufferAndCurrentSegment(
  NS_ASSERTION(IsParserThread(), "Wrong thread!");
  nsresult rv = NS_OK;
  if (mDecodingLocalFileWithoutTokenizing &&
-      mCharsetSource <= kCharsetFromTopLevelDomain) {
+      mCharsetSource <= kCharsetFromFallback) {
    MOZ_ASSERT(mEncoding != UTF_8_ENCODING);
    mUnicodeDecoder = UTF_8_ENCODING->NewDecoderWithBOMRemoval();
  } else {
-    if (mCharsetSource >= kCharsetFromFinalJapaneseAutoDetection) {
-      if (!(mCharsetSource == kCharsetFromUserForced ||
-            mCharsetSource == kCharsetFromPendingUserForcedAutoDetection ||
+    if (mCharsetSource >= kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8) {
+      if (!(mCharsetSource == kCharsetFromPendingUserForcedAutoDetection ||
            mCharsetSource == kCharsetFromInitialUserForcedAutoDetection)) {
        DontGuessEncoding();
      }
@ -681,7 +639,7 @@ nsresult nsHtml5StreamParser::FinalizeSniffing(Span<const uint8_t> aFromSegment,
                                               uint32_t aCountToSniffingLimit,
                                               bool aEof) {
  MOZ_ASSERT(IsParserThread(), "Wrong thread!");
-  MOZ_ASSERT(mCharsetSource < kCharsetFromUserForcedJapaneseAutoDetection,
+  MOZ_ASSERT(mCharsetSource < kCharsetFromXmlDeclarationUtf16,
             "Should not finalize sniffing with strong decision already made.");
  if (mMode == VIEW_SOURCE_XML) {
    static const XML_Memory_Handling_Suite memsuite = {
@ -744,12 +702,9 @@ nsresult nsHtml5StreamParser::FinalizeSniffing(Span<const uint8_t> aFromSegment,

    return SetupDecodingAndWriteSniffingBufferAndCurrentSegment(aFromSegment);
  }
-  bool forced =
-      (mCharsetSource == kCharsetFromUserForced ||
-       mCharsetSource == kCharsetFromUserForcedJapaneseAutoDetection ||
-       mCharsetSource == kCharsetFromPendingUserForcedAutoDetection ||
-       mCharsetSource == kCharsetFromInitialUserForcedAutoDetection ||
-       mCharsetSource == kCharsetFromFinalUserForcedAutoDetection);
+  bool forced = (mCharsetSource == kCharsetFromPendingUserForcedAutoDetection ||
+                 mCharsetSource == kCharsetFromInitialUserForcedAutoDetection ||
+                 mCharsetSource == kCharsetFromFinalUserForcedAutoDetection);
  if (!mChannelHadCharset &&
      (forced || mCharsetSource < kCharsetFromMetaPrescan) &&
      (mMode == NORMAL || mMode == VIEW_SOURCE_HTML || mMode == LOAD_AS_DATA)) {
@ -776,17 +731,7 @@ nsresult nsHtml5StreamParser::FinalizeSniffing(Span<const uint8_t> aFromSegment,
      if (forced &&
          (encoding->IsAsciiCompatible() || encoding == ISO_2022_JP_ENCODING)) {
        // Honor override
-        if (mCharsetSource == kCharsetFromUserForced &&
-            mEncoding->IsJapaneseLegacy()) {
-          mFeedChardet = true;
-          if (!mJapaneseDetector) {
-            mJapaneseDetector = mozilla::JapaneseDetector::Create(true);
-          }
-          FinalizeSniffingWithDetector(aFromSegment, aCountToSniffingLimit,
-                                       false);
-        } else if (mCharsetSource ==
-                       kCharsetFromUserForcedJapaneseAutoDetection ||
-                   mCharsetSource == kCharsetFromFinalUserForcedAutoDetection) {
+        if (mCharsetSource == kCharsetFromFinalUserForcedAutoDetection) {
          DontGuessEncoding();
        } else {
          FinalizeSniffingWithDetector(aFromSegment, aCountToSniffingLimit,
@ -808,15 +753,7 @@ nsresult nsHtml5StreamParser::FinalizeSniffing(Span<const uint8_t> aFromSegment,
  }
  if (forced && mCharsetSource != kCharsetFromIrreversibleAutoDetection) {
    // neither meta nor XML declaration found, honor override
-    if (mCharsetSource == kCharsetFromUserForced &&
-        mEncoding->IsJapaneseLegacy()) {
-      mFeedChardet = true;
-      if (!mJapaneseDetector) {
-        mJapaneseDetector = mozilla::JapaneseDetector::Create(true);
-      }
-      FinalizeSniffingWithDetector(aFromSegment, aCountToSniffingLimit, false);
-    } else if (mCharsetSource == kCharsetFromUserForcedJapaneseAutoDetection ||
-               mCharsetSource == kCharsetFromFinalUserForcedAutoDetection) {
+    if (mCharsetSource == kCharsetFromFinalUserForcedAutoDetection) {
      DontGuessEncoding();
    } else {
      FinalizeSniffingWithDetector(aFromSegment, aCountToSniffingLimit, false);
@ -1021,9 +958,7 @@ nsresult nsHtml5StreamParser::SniffStreamBytes(
    // this is the last buffer
    uint32_t countToSniffingLimit = SNIFFING_BUFFER_SIZE - mSniffingLength;
    bool forced =
-        (mCharsetSource == kCharsetFromUserForced ||
-         mCharsetSource == kCharsetFromUserForcedJapaneseAutoDetection ||
-         mCharsetSource == kCharsetFromPendingUserForcedAutoDetection ||
+        (mCharsetSource == kCharsetFromPendingUserForcedAutoDetection ||
         mCharsetSource == kCharsetFromInitialUserForcedAutoDetection ||
         mCharsetSource == kCharsetFromFinalUserForcedAutoDetection);
    if (!mChannelHadCharset && (mMode == NORMAL || mMode == VIEW_SOURCE_HTML ||
@ -1045,18 +980,7 @@ nsresult nsHtml5StreamParser::SniffStreamBytes(
        if (forced && (encoding->IsAsciiCompatible() ||
                       encoding == ISO_2022_JP_ENCODING)) {
          // Honor override
-          if (mCharsetSource == kCharsetFromUserForced &&
-              mEncoding->IsJapaneseLegacy()) {
-            mFeedChardet = true;
-            if (!mJapaneseDetector) {
-              mJapaneseDetector = mozilla::JapaneseDetector::Create(true);
-            }
-            FinalizeSniffingWithDetector(aFromSegment, countToSniffingLimit,
-                                         false);
-          } else if (mCharsetSource ==
-                         kCharsetFromUserForcedJapaneseAutoDetection ||
-                     mCharsetSource ==
-                         kCharsetFromFinalUserForcedAutoDetection) {
+          if (mCharsetSource == kCharsetFromFinalUserForcedAutoDetection) {
            DontGuessEncoding();
          } else {
            FinalizeSniffingWithDetector(aFromSegment, countToSniffingLimit,
@ -1091,9 +1015,7 @@ nsresult nsHtml5StreamParser::SniffStreamBytes(
    }
    if (encoding) {
      // meta scan successful; honor overrides unless meta is XSS-dangerous
-      if ((mCharsetSource == kCharsetFromUserForced ||
-           mCharsetSource == kCharsetFromUserForcedJapaneseAutoDetection ||
-           mCharsetSource == kCharsetFromFinalUserForcedAutoDetection) &&
+      if ((mCharsetSource == kCharsetFromFinalUserForcedAutoDetection) &&
          (encoding->IsAsciiCompatible() || encoding == ISO_2022_JP_ENCODING)) {
        // Honor override
        return SetupDecodingAndWriteSniffingBufferAndCurrentSegment(
@ -1293,7 +1215,7 @@ nsresult nsHtml5StreamParser::OnStartRequest(nsIRequest* aRequest) {
  // let's instantiate only if we make it out of this method with the
  // intent to use it.
  auto detectorCreator = MakeScopeExit([&] {
-    if (mFeedChardet && !mJapaneseDetector) {
+    if (mFeedChardet) {
      mDetector = mozilla::EncodingDetector::Create();
    }
  });
@ -1321,7 +1243,7 @@ nsresult nsHtml5StreamParser::OnStartRequest(nsIRequest* aRequest) {
  nsresult rv = GetChannel(getter_AddRefs(channel));
  if (NS_SUCCEEDED(rv)) {
    isSrcdoc = NS_IsSrcdocChannel(channel);
-    if (!isSrcdoc && mCharsetSource <= kCharsetFromTopLevelDomain) {
+    if (!isSrcdoc && mCharsetSource <= kCharsetFromFallback) {
      nsCOMPtr<nsIURI> originalURI;
      rv = channel->GetOriginalURI(getter_AddRefs(originalURI));
      if (NS_SUCCEEDED(rv)) {
@ -1457,44 +1379,8 @@ nsresult nsHtml5StreamParser::OnStartRequest(nsIRequest* aRequest) {
  if (!(mCharsetSource == kCharsetFromPendingUserForcedAutoDetection ||
        mCharsetSource == kCharsetFromInitialUserForcedAutoDetection ||
        mCharsetSource == kCharsetFromFinalUserForcedAutoDetection)) {
-    if (mCharsetSource >= kCharsetFromFinalJapaneseAutoDetection) {
-      if ((mCharsetSource == kCharsetFromUserForced) &&
-          mEncoding->IsJapaneseLegacy()) {
-        // Japanese detector only
-        if (!mJapaneseDetector) {
-          mJapaneseDetector = mozilla::JapaneseDetector::Create(true);
-        }
-        mGuessEncoding = false;
-      } else {
-        DontGuessEncoding();
-      }
-    }
-
-    // Compute various pref-based special cases
-    if (!mDecodingLocalFileWithoutTokenizing && mFeedChardet) {
-      if (mTLD.EqualsLiteral("jp")) {
-        if (!mJapaneseDetector &&
-            !StaticPrefs::intl_charset_detector_ng_jp_enabled()) {
-          mJapaneseDetector = mozilla::JapaneseDetector::Create(true);
-        }
-        if (mJapaneseDetector && mEncoding == WINDOWS_1252_ENCODING &&
-            mCharsetSource <= kCharsetFromTopLevelDomain) {
-          mCharsetSource = kCharsetFromTopLevelDomain;
-          mEncoding = SHIFT_JIS_ENCODING;
-          mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource);
-        }
-      } else if ((mTLD.EqualsLiteral("in") &&
-                  !StaticPrefs::intl_charset_detector_ng_in_enabled()) ||
-                 (mTLD.EqualsLiteral("lk") &&
-                  !StaticPrefs::intl_charset_detector_ng_lk_enabled())) {
-        if (mEncoding == WINDOWS_1252_ENCODING &&
-            mCharsetSource <= kCharsetFromTopLevelDomain) {
-          // Avoid breaking font hacks that Chrome doesn't break.
-          mCharsetSource = kCharsetFromTopLevelDomain;
-          mTreeBuilder->SetDocumentCharset(mEncoding, mCharsetSource);
-        }
-        DontGuessEncoding();
-      }
+    if (mCharsetSource >= kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8) {
+      DontGuessEncoding();
    }
  }

--- a/parser/html/nsHtml5StreamParser.h
+++ b/parser/html/nsHtml5StreamParser.h
@ -45,7 +45,6 @@ class nsIURI;

 namespace mozilla {
 class EncodingDetector;
-class JapaneseDetector;
 template <typename T>
 class Buffer;

@ -219,11 +218,6 @@ class nsHtml5StreamParser final : public nsISupports {

  // Not from an external interface

-  /**
-   * Pass a buffer to the JapaneseDetector.
-   */
-  void FeedJapaneseDetector(mozilla::Span<const uint8_t> aBuffer, bool aLast);
-
  /**
   * Pass a buffer to the Japanese or Cyrillic detector as appropriate.
   */
@ -658,11 +652,6 @@ class nsHtml5StreamParser final : public nsISupports {

  nsCOMPtr<nsIRunnable> mLoadFlusher;

-  /**
-   * The Japanese detector.
-   */
-  mozilla::UniquePtr<mozilla::JapaneseDetector> mJapaneseDetector;
-
  /**
   * The generict detector.
   */
--- a/parser/nsCharsetSource.h
+++ b/parser/nsCharsetSource.h
@ -9,7 +9,6 @@
 enum {
  kCharsetUninitialized,
  kCharsetFromFallback,
-  kCharsetFromTopLevelDomain,
  kCharsetFromDocTypeDefault,  // This and up confident for XHR
  // Start subdividing source for telementry purposes
  kCharsetFromInitialAutoDetectionASCII,
@ -17,7 +16,6 @@ enum {
  kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8Generic,
  kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8Content,
  kCharsetFromInitialAutoDetectionWouldNotHaveBeenUTF8DependedOnTLD,
-  kCharsetFromFinalJapaneseAutoDetection,
  // Deliberately no Final version of ASCII
  kCharsetFromFinalAutoDetectionWouldHaveBeenUTF8,
  kCharsetFromFinalAutoDetectionWouldNotHaveBeenUTF8Generic,
@ -37,8 +35,6 @@ enum {
                                               // later
  kCharsetFromInitialUserForcedAutoDetection,
  kCharsetFromFinalUserForcedAutoDetection,
-  kCharsetFromUserForced,  // propagates to child frames
-  kCharsetFromUserForcedJapaneseAutoDetection,
  kCharsetFromXmlDeclarationUtf16,        // This one is overridden by
                                          // kCharsetFromChannel
  kCharsetFromIrreversibleAutoDetection,  // This one is overridden by
--- a/third_party/rust/shift_or_euc/.cargo-checksum.json
+++ b/third_party/rust/shift_or_euc/.cargo-checksum.json
@ -1 +0,0 @@
-{"files":{"CONTRIBUTING.md":"0e64fb3dd5a00e3fd528de6442de3f2ca851bd718c45cca0871aaf4eedac9ee1","COPYRIGHT":"3a7313aa2f19bf7095a2fd731c3d5e76f38d5e4640bd2a115d53032f24b2aa6c","Cargo.toml":"f9f41b76ecbe257a312ab09ed1208189b8dc9952d12d17a216fe2846d1d471c8","LICENSE-APACHE":"cfc7749b96f63bd31c3c42b5c471bf756814053e847c10f3eb003417bc523d30","LICENSE-MIT":"dac4dde23582d18b01701032860d8f8a1979fb2cf626060ca8de77e081a2a3d5","README.md":"b7148745a7ef59788e76fbe638d4b41c54dcaa1313a809f4630a020645f892a8","examples/detect.rs":"eb7239ccc802290ef24331db600ca1226198801dd86df86876b4b738ef4b8470","src/lib.rs":"f2a83db125d553af5c6fabae0487ef211aad62f2d93c4418dc510cbd425d472a"},"package":"f930dea4685b9803954b9d74cdc175c6d946a22f2eafe5aa2e9a58cdcae7da8c"}
--- a/third_party/rust/shift_or_euc/CONTRIBUTING.md
+++ b/third_party/rust/shift_or_euc/CONTRIBUTING.md
@ -1,38 +0,0 @@
-If you send a pull request / patch, please observe the following.
-
-## Licensing
-
-Since this crate is dual-licensed,
-[section 5 of the Apache License 2.0](https://www.apache.org/licenses/LICENSE-2.0#contributions)
-is considered to apply in the sense of Contributions being automatically
-under the Apache License 2.0 or MIT dual license (see the `COPYRIGHT` file).
-That is, by the act of offering a Contribution, you place your Contribution
-under the Apache License 2.0 or MIT dual license stated in the `COPYRIGHT`
-file. Please do not contribute if you aren't willing or allowed to license your
-contributions in this manner.
-
-You are encouraged to dedicate test code that you contribute to the Public
-Domain using the CC0 dedication. If you contribute test code that is not
-dedicated to the Public Domain, please be sure not to put it in a part of
-source code that the comments designate as being dedicated to the Public
-Domain.
-
-## Copyright Notices
-
-If you require the addition of your copyright notice, it's up to you to edit in
-your notice as part of your Contribution. Not adding a copyright notice is
-taken as a waiver of copyright notice.
-
-## Compatibility with Stable Rust
-
-Please ensure that your Contribution compiles with the latest stable-channel
-rustc.
-
-## rustfmt
-
-The `rustfmt` version used for this code is `rustfmt-nightly`. Please either
-use that version or avoid using `rustfmt` (so as not to reformat all the code).
-
-## Unit tests
-
-Please ensure that `cargo test` succeeds.
--- a/third_party/rust/shift_or_euc/COPYRIGHT
+++ b/third_party/rust/shift_or_euc/COPYRIGHT
@ -1,9 +0,0 @@
-shift_or_euc is copyright 2018 Mozilla Foundation.
-
-Licensed under the Apache License, Version 2.0
-<LICENSE-APACHE or
-https://www.apache.org/licenses/LICENSE-2.0> or the MIT
-license <LICENSE-MIT or https://opensource.org/licenses/MIT>,
-at your option. All files in the project carrying such
-notice may not be copied, modified, or distributed except
-according to those terms.
--- a/third_party/rust/shift_or_euc/Cargo.toml
+++ b/third_party/rust/shift_or_euc/Cargo.toml
@ -1,30 +0,0 @@
-# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
-#
-# When uploading crates to the registry Cargo will automatically
-# "normalize" Cargo.toml files for maximal compatibility
-# with all versions of Cargo and also rewrite `path` dependencies
-# to registry (e.g., crates.io) dependencies
-#
-# If you believe there's an error in this file please file an
-# issue against the rust-lang/cargo repository. If you're
-# editing this file be aware that the upstream Cargo.toml
-# will likely look very different (and much more reasonable)
-
-[package]
-edition = "2018"
-name = "shift_or_euc"
-version = "0.1.0"
-authors = ["Henri Sivonen <hsivonen@hsivonen.fi>"]
-description = "Detects among the Japanese legacy encodings"
-homepage = "https://docs.rs/shift_or_euc/"
-documentation = "https://docs.rs/shift_or_euc/"
-readme = "README.md"
-keywords = ["encoding", "web", "charset"]
-categories = ["text-processing", "encoding", "web-programming", "internationalization"]
-license = "MIT/Apache-2.0"
-repository = "https://github.com/hsivonen/shift_or_euc"
-[dependencies.encoding_rs]
-version = "0.8.17"
-
-[dependencies.memchr]
-version = "2.2.0"
--- a/third_party/rust/shift_or_euc/LICENSE-APACHE
+++ b/third_party/rust/shift_or_euc/LICENSE-APACHE
@ -1,202 +0,0 @@
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-
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--- a/third_party/rust/shift_or_euc/LICENSE-MIT
+++ b/third_party/rust/shift_or_euc/LICENSE-MIT
@ -1,25 +0,0 @@
-Copyright (c) 2018 Mozilla Foundation
-
-Permission is hereby granted, free of charge, to any
-person obtaining a copy of this software and associated
-documentation files (the "Software"), to deal in the
-Software without restriction, including without
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-The above copyright notice and this permission notice
-shall be included in all copies or substantial portions
-of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
-ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
-TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
-PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
-SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
-CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
-IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
-DEALINGS IN THE SOFTWARE.
--- a/third_party/rust/shift_or_euc/README.md
+++ b/third_party/rust/shift_or_euc/README.md
@ -1,73 +0,0 @@
-# shift_or_euc
-
-[![Apache 2 / MIT dual-licensed](https://img.shields.io/badge/license-Apache%202%20%2F%20MIT-blue.svg)](https://github.com/hsivonen/shift_or_euc/blob/master/COPYRIGHT)
-
-A Japanese legacy encoding detector for detecting between Shift_JIS, EUC-JP,
-and, optionally, ISO-2022-JP _given_ the assumption that the encoding is one
-of those.
-
-This detector is generally more accurate (but see below about the failure
-mode on half-width katakana) and decides much sooner than machine
-learning-based detectors. To decide EUC-JP, machine learning-based detectors
-try to gain confidence that the input looks like EUC-JP. To decide EUC-JP,
-this detector instead looks for two simple rule-based signs of the input not
-being Shift_JIS.
-
-As a consequence of not containing machine learning tables, the binary size
-footprint that this crate adds on top of
-[`encoding_rs`](https://docs.rs/crate/encoding_rs) is tiny.
-
-## Documentation
-
-[API documentation on docs.rs](https://docs.rs/crate/shift_or_euc)
-
-## Licensing
-
-See the file named [COPYRIGHT](https://github.com/hsivonen/shift_or_euc/blob/master/COPYRIGHT).
-
-## Sample Program Usage
-
-1. [Install Rust](https://rustup.rs/)
-2. `git clone https://github.com/hsivonen/shift_or_euc`
-3. `cd shift_or_euc`
-4. `cargo run --example detect PATH_TO_FILE`
-
-The program prints one of:
-
-* Shift_JIS
-* EUC-JP
-* ISO-2022-JP
-* Undecided
-
-## Principle of Operation
-
-The detector is based on two observations:
-
-1. The ISO-2022-JP escape sequences don't normally occur in Shift_JIS or
-EUC-JP, so encountering such an escape sequence (before non-ASCII has been
-encountered) can be taken as indication of ISO-2022-JP.
-2. When normal (full-with) kana or common kanji encoded as Shift_JIS is
-decoded as EUC-JP, or vice versa, the result is either an error or half-width
-katakana, and it's very uncommon for Japanese HTML to have half-width katakana
-character before a normal kana or common kanji character. Therefore, if
-decoding as Shift_JIS results in error or have-width katakana, the detector
-decides that the content is EUC-JP, and vice versa.
-
-## Failure Modes
-
-The detector gives the wrong answer if the text has a half-width katakana
-character before normal kana or common kanji. Some uncommon kanji are
-undecidable. (All JIS X 0208 Level 1 kanji are decidable.)
-
-The half-width katakana issue is mainly relevant for old 8-bit JIS X 0201-only
-text files that would decode correctly as Shift_JIS but that the detector
-detects as EUC-JP.
-
-The undecidable kanji issue does not realistically show up when a full
-document is fed to the detector, because, realistically, in a full document,
-there is at least one kana or common kanji. It can occur, though, if the
-detector is only run on a prefix of a document and the prefix only contains
-the title of the document. It is possible for document title to consist
-entirely of undecidable kanji. (Indeed, Japanese Wikipedia has articles with
-such titles.) If the detector is undecided, falling back to Shift_JIS is
-typically the Web oriented better guess.
--- a/third_party/rust/shift_or_euc/examples/detect.rs
+++ b/third_party/rust/shift_or_euc/examples/detect.rs
@ -1,56 +0,0 @@
-// Copyright 2018 Mozilla Foundation. See the COPYRIGHT
-// file at the top-level directory of this distribution.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-use std::fs::File;
-use std::io::Read;
-
-use shift_or_euc::Detector;
-
-fn main() {
-    let mut args = std::env::args_os();
-    if args.next().is_none() {
-        eprintln!("Error: Program name missing from arguments.");
-        std::process::exit(-1);
-    }
-    if let Some(path) = args.next() {
-        if args.next().is_some() {
-            eprintln!("Error: Too many arguments.");
-            std::process::exit(-3);
-        }
-        if let Ok(mut file) = File::open(path) {
-            let mut buffer = [0u8; 4096];
-            let mut detector = Detector::new(true);
-            loop {
-                if let Ok(num_read) = file.read(&mut buffer[..]) {
-                    let opt_enc = if num_read == 0 {
-                        detector.feed(b"", true)
-                    } else {
-                        detector.feed(&buffer[..num_read], false)
-                    };
-                    if let Some(encoding) = opt_enc {
-                        println!("{}", encoding.name());
-                        return;
-                    } else if num_read == 0 {
-                        println!("Undecided");
-                        return;
-                    }
-                } else {
-                    eprintln!("Error: Error reading file.");
-                    std::process::exit(-5);
-                }
-            }
-        } else {
-            eprintln!("Error: Could not open file.");
-            std::process::exit(-4);
-        }
-    } else {
-        eprintln!("Error: One path argument needed.");
-        std::process::exit(-2);
-    }
-}
--- a/third_party/rust/shift_or_euc/src/lib.rs
+++ b/third_party/rust/shift_or_euc/src/lib.rs
@ -1,278 +0,0 @@
-// Copyright 2018 Mozilla Foundation. See the COPYRIGHT
-// file at the top-level directory of this distribution.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#![doc(html_root_url = "https://docs.rs/shift_or_euc/0.1.0")]
-
-//! A Japanese legacy encoding detector for detecting between Shift_JIS,
-//! EUC-JP, and, optionally, ISO-2022-JP _given_ the assumption that the
-//! encoding is one of those.
-//!
-//! This detector is generally more accurate (but see below about the failure
-//! mode on half-width katakana) and decides much sooner than machine
-//! learning-based detectors. To decide EUC-JP, machine learning-based
-//! detectors try to gain confidence that the input looks like EUC-JP. To
-//! decide EUC-JP, this detector instead looks for two simple rule-based
-//! signs of the input not being Shift_JIS.
-//!
-//! As a consequence of not containing machine learning tables, the binary
-//! size footprint that this crate adds on top of
-//! [`encoding_rs`](https://docs.rs/crate/encoding_rs) is tiny.
-//!
-//! # Licensing
-//!
-//! See the file named [COPYRIGHT](https://github.com/hsivonen/shift_or_euc/blob/master/COPYRIGHT).
-//!
-//! # Principle of Operation
-//!
-//! The detector is based on two observations:
-//!
-//! 1. The ISO-2022-JP escape sequences don't normally occur in Shift_JIS or
-//! EUC-JP, so encountering such an escape sequence (before non-ASCII has been
-//! encountered) can be taken as indication of ISO-2022-JP.
-//! 2. When normal (full-with) kana or common kanji encoded as Shift_JIS is
-//! decoded as EUC-JP, or vice versa, the result is either an error or
-//! half-width katakana, and it's very uncommon for Japanese HTML to have
-//! half-width katakana character before a normal kana or common kanji
-//! character. Therefore, if decoding as Shift_JIS results in error or
-//! have-width katakana, the detector decides that the content is EUC-JP, and
-//! vice versa.
-//!
-//! # Failure Modes
-//!
-//! The detector gives the wrong answer if the text has a half-width katakana
-//! character before normal kana or common kanji. Some uncommon kanji are
-//! undecidable. (All JIS X 0208 Level 1 kanji are decidable.)
-//!
-//! The half-width katakana issue is mainly relevant for old 8-bit JIS X
-//! 0201-only text files that would decode correctly as Shift_JIS but that the
-//!  detector detects as EUC-JP.
-//!
-//! The undecidable kanji issue does not realistically show up when a full
-//! document is fed to the detector, because, realistically, in a full
-//! document, there is at least one kana or common kanji. It can occur,
-//! though, if the detector is only run on a prefix of a document and the
-//! prefix only contains the title of the document. It is possible for
-//! document title to consist entirely of undecidable kanji. (Indeed,
-//! Japanese Wikipedia has articles with such titles.) If the detector is
-//! undecided, falling back to Shift_JIS is typically the Web oriented better
-//! guess.
-
-use encoding_rs::Decoder;
-use encoding_rs::DecoderResult;
-use encoding_rs::Encoding;
-use encoding_rs::EUC_JP;
-use encoding_rs::ISO_2022_JP;
-use encoding_rs::SHIFT_JIS;
-
-/// Returns the index of the first non-ASCII byte or the first
-/// 0x1B, whichever comes first, or the length of the buffer
-/// if neither is found.
-fn find_non_ascii_or_escape(buffer: &[u8]) -> usize {
-    let ascii_up_to = Encoding::ascii_valid_up_to(buffer);
-    if let Some(escape) = memchr::memchr(0x1B, &buffer[..ascii_up_to]) {
-        escape
-    } else {
-        ascii_up_to
-    }
-}
-
-/// Feed decoder with one byte (if `last` is `false`) or EOF (if `last` is
-/// `true`). `byte` is ignored if `last` is `true`.
-/// Returns `true` if there was no rejection or `false` upon rejecting the
-/// encoding hypothesis represented by this decoder.
-#[inline(always)]
-fn feed_decoder(decoder: &mut Decoder, byte: u8, last: bool) -> bool {
-    let mut output = [0u16; 1];
-    let input = [byte];
-    let (result, _read, written) = decoder.decode_to_utf16_without_replacement(
-        if last { b"" } else { &input },
-        &mut output,
-        last,
-    );
-    match result {
-        DecoderResult::InputEmpty => {
-            if written == 1 {
-                match output[0] {
-                    0xFF61...0xFF9F => {
-                        return false;
-                    }
-                    _ => {}
-                }
-            }
-        }
-        DecoderResult::Malformed(_, _) => {
-            return false;
-        }
-        DecoderResult::OutputFull => {
-            unreachable!();
-        }
-    }
-    true
-}
-
-/// A detector for detecting the character encoding of input on the
-/// precondition that the encoding is a Japanese legacy encoding.
-pub struct Detector {
-    shift_jis_decoder: Decoder,
-    euc_jp_decoder: Decoder,
-    second_byte_in_escape: u8,
-    iso_2022_jp_disqualified: bool,
-    escape_seen: bool,
-    finished: bool,
-}
-
-impl Detector {
-    /// Instantiates the detector. If `allow_2022` is `true` the possible
-    /// guesses are Shift_JIS, EUC-JP, ISO-2022-JP, and undecided. If
-    /// `allow_2022` is `false`, the possible guesses are Shift_JIS, EUC-JP,
-    /// and undecided.
-    pub fn new(allow_2022: bool) -> Self {
-        Detector {
-            shift_jis_decoder: SHIFT_JIS.new_decoder_without_bom_handling(),
-            euc_jp_decoder: EUC_JP.new_decoder_without_bom_handling(),
-            second_byte_in_escape: 0,
-            iso_2022_jp_disqualified: !allow_2022,
-            escape_seen: false,
-            finished: false,
-        }
-    }
-
-    /// Feeds bytes to the detector. If `last` is `true` the end of the stream
-    /// is considered to occur immediately after the end of `buffer`.
-    /// Otherwise, the stream is expected to continue. `buffer` may be empty.
-    ///
-    /// If you're running the detector only on a prefix of a complete
-    /// document, _do not_ pass `last` as `true` after the prefix if the
-    /// stream as a whole still contains more content.
-    ///
-    /// Returns `Some(encoding_rs::SHIFT_JIS)` if the detector guessed
-    /// Shift_JIS. Returns `Some(encoding_rs::EUC_JP)` if the detector
-    /// guessed EUC-JP. Returns `Some(encoding_rs::ISO_2022_JP)` if the
-    /// detector guessed ISO-2022-JP (only possible if `true` was passed as
-    /// `allow_2022` when instantiating the detector). Returns `None` if the
-    /// detector is undecided. If `None` is returned even when passing `true`
-    /// as `last`, falling back to Shift_JIS is the best guess for Web
-    /// purposes.
-    ///
-    /// Do not call again after the method has returned `Some(_)` or after
-    /// the method has been called with `true` as `last`.
-    ///
-    /// # Panics
-    ///
-    /// If called after the method has returned `Some(_)` or after the method
-    /// has been called with `true` as `last`.
-    pub fn feed(&mut self, buffer: &[u8], last: bool) -> Option<&'static Encoding> {
-        assert!(
-            !self.finished,
-            "Tried to used a detector that has finished."
-        );
-        self.finished = true; // Will change back to false unless we return early
-        let mut i = 0;
-        if !self.iso_2022_jp_disqualified {
-            if !self.escape_seen {
-                i = find_non_ascii_or_escape(buffer);
-            }
-            while i < buffer.len() {
-                let byte = buffer[i];
-                if byte > 0x7F {
-                    self.iso_2022_jp_disqualified = true;
-                    break;
-                }
-                if !self.escape_seen && byte == 0x1B {
-                    self.escape_seen = true;
-                    i += 1;
-                    continue;
-                }
-                if self.escape_seen && self.second_byte_in_escape == 0 {
-                    self.second_byte_in_escape = byte;
-                    i += 1;
-                    continue;
-                }
-                match (self.second_byte_in_escape, byte) {
-                    (0x28, 0x42) | (0x28, 0x4A) | (0x28, 0x49) | (0x24, 0x40) | (0x24, 0x42) => {
-                        return Some(ISO_2022_JP);
-                    }
-                    _ => {}
-                }
-                if self.escape_seen {
-                    self.iso_2022_jp_disqualified = true;
-                    break;
-                }
-                i += 1;
-            }
-        }
-        for &byte in &buffer[i..] {
-            if !feed_decoder(&mut self.euc_jp_decoder, byte, false) {
-                return Some(SHIFT_JIS);
-            }
-            if !feed_decoder(&mut self.shift_jis_decoder, byte, false) {
-                return Some(EUC_JP);
-            }
-        }
-        if last {
-            if !feed_decoder(&mut self.euc_jp_decoder, 0, true) {
-                return Some(SHIFT_JIS);
-            }
-            if !feed_decoder(&mut self.shift_jis_decoder, 0, true) {
-                return Some(EUC_JP);
-            }
-            return None;
-        }
-        self.finished = false;
-        None
-    }
-}
-
-// Any copyright to the test code below this comment is dedicated to the
-// Public Domain. http://creativecommons.org/publicdomain/zero/1.0/
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    #[test]
-    fn test_iso_2022_jp() {
-        let mut detector = Detector::new(true);
-        assert_eq!(
-            detector.feed(b"abc\x1B\x28\x42\xFF", true),
-            Some(ISO_2022_JP)
-        );
-    }
-
-    #[test]
-    fn test_error_precedence() {
-        let mut detector = Detector::new(true);
-        assert_eq!(detector.feed(b"abc\xFF", true), Some(SHIFT_JIS));
-    }
-
-    #[test]
-    fn test_invalid_euc_jp() {
-        let mut detector = Detector::new(true);
-        assert_eq!(detector.feed(b"abc\x81\x40", true), Some(SHIFT_JIS));
-    }
-
-    #[test]
-    fn test_invalid_shift_jis() {
-        let mut detector = Detector::new(true);
-        assert_eq!(detector.feed(b"abc\xEB\xA8", true), Some(EUC_JP));
-    }
-
-    #[test]
-    fn test_invalid_shift_jis_before_invalid_euc_jp() {
-        let mut detector = Detector::new(true);
-        assert_eq!(detector.feed(b"abc\xEB\xA8\x81\x40", true), Some(EUC_JP));
-    }
-
-    #[test]
-    fn test_undecided() {
-        let mut detector = Detector::new(true);
-        assert_eq!(detector.feed(b"abc", false), None);
-        assert_eq!(detector.feed(b"abc", false), None);
-    }
-
-}
--- a/third_party/rust/shift_or_euc_c/.cargo-checksum.json
+++ b/third_party/rust/shift_or_euc_c/.cargo-checksum.json
@ -1 +0,0 @@
-{"files":{"CONTRIBUTING.md":"0e64fb3dd5a00e3fd528de6442de3f2ca851bd718c45cca0871aaf4eedac9ee1","COPYRIGHT":"3a7313aa2f19bf7095a2fd731c3d5e76f38d5e4640bd2a115d53032f24b2aa6c","Cargo.toml":"342e5345f4fb433b89f397b07e4e7162376b30cbbc1d6f6ccb11523116e6ed6b","LICENSE-APACHE":"cfc7749b96f63bd31c3c42b5c471bf756814053e847c10f3eb003417bc523d30","LICENSE-MIT":"dac4dde23582d18b01701032860d8f8a1979fb2cf626060ca8de77e081a2a3d5","README.md":"a323f1f4537bc7b3f9b3b216c8ac5041b83aa0321f5349a52627aade947c6272","include/shift_or_euc.h":"47c3b9832cb7eb8995aa37dcc2e76be7d4f5c7b3fa6b43135e579831ab449cd8","src/lib.rs":"cab1898dd6724e0a0324a1e44f6348c107f13916da8873dba69c70dbc95ba9cd"},"package":"c81ec08c8a68c45c48d8ef58b80ce038cc9945891c4a4996761e2ec5cba05abc"}
--- a/third_party/rust/shift_or_euc_c/CONTRIBUTING.md
+++ b/third_party/rust/shift_or_euc_c/CONTRIBUTING.md
@ -1,38 +0,0 @@
-If you send a pull request / patch, please observe the following.
-
-## Licensing
-
-Since this crate is dual-licensed,
-[section 5 of the Apache License 2.0](https://www.apache.org/licenses/LICENSE-2.0#contributions)
-is considered to apply in the sense of Contributions being automatically
-under the Apache License 2.0 or MIT dual license (see the `COPYRIGHT` file).
-That is, by the act of offering a Contribution, you place your Contribution
-under the Apache License 2.0 or MIT dual license stated in the `COPYRIGHT`
-file. Please do not contribute if you aren't willing or allowed to license your
-contributions in this manner.
-
-You are encouraged to dedicate test code that you contribute to the Public
-Domain using the CC0 dedication. If you contribute test code that is not
-dedicated to the Public Domain, please be sure not to put it in a part of
-source code that the comments designate as being dedicated to the Public
-Domain.
-
-## Copyright Notices
-
-If you require the addition of your copyright notice, it's up to you to edit in
-your notice as part of your Contribution. Not adding a copyright notice is
-taken as a waiver of copyright notice.
-
-## Compatibility with Stable Rust
-
-Please ensure that your Contribution compiles with the latest stable-channel
-rustc.
-
-## rustfmt
-
-The `rustfmt` version used for this code is `rustfmt-nightly`. Please either
-use that version or avoid using `rustfmt` (so as not to reformat all the code).
-
-## Unit tests
-
-Please ensure that `cargo test` succeeds.
--- a/third_party/rust/shift_or_euc_c/COPYRIGHT
+++ b/third_party/rust/shift_or_euc_c/COPYRIGHT
@ -1,9 +0,0 @@
-shift_or_euc is copyright 2018 Mozilla Foundation.
-
-Licensed under the Apache License, Version 2.0
-<LICENSE-APACHE or
-https://www.apache.org/licenses/LICENSE-2.0> or the MIT
-license <LICENSE-MIT or https://opensource.org/licenses/MIT>,
-at your option. All files in the project carrying such
-notice may not be copied, modified, or distributed except
-according to those terms.
--- a/third_party/rust/shift_or_euc_c/Cargo.toml
+++ b/third_party/rust/shift_or_euc_c/Cargo.toml
@ -1,30 +0,0 @@
-# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
-#
-# When uploading crates to the registry Cargo will automatically
-# "normalize" Cargo.toml files for maximal compatibility
-# with all versions of Cargo and also rewrite `path` dependencies
-# to registry (e.g., crates.io) dependencies
-#
-# If you believe there's an error in this file please file an
-# issue against the rust-lang/cargo repository. If you're
-# editing this file be aware that the upstream Cargo.toml
-# will likely look very different (and much more reasonable)
-
-[package]
-edition = "2018"
-name = "shift_or_euc_c"
-version = "0.1.0"
-authors = ["Henri Sivonen <hsivonen@hsivonen.fi>"]
-description = "C API for shift_or_euc"
-homepage = "https://docs.rs/shift_or_euc_c/"
-documentation = "https://docs.rs/shift_or_euc_c/"
-readme = "README.md"
-keywords = ["encoding", "web", "charset"]
-categories = ["text-processing", "encoding", "web-programming", "internationalization"]
-license = "MIT/Apache-2.0"
-repository = "https://github.com/hsivonen/shift_or_euc_c"
-[dependencies.encoding_rs]
-version = "0.8.17"
-
-[dependencies.shift_or_euc]
-version = "0.1.0"
--- a/third_party/rust/shift_or_euc_c/LICENSE-APACHE
+++ b/third_party/rust/shift_or_euc_c/LICENSE-APACHE
@ -1,202 +0,0 @@
-
-                                 Apache License
-                           Version 2.0, January 2004
-                        http://www.apache.org/licenses/
-
-   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
-
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-
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--- a/third_party/rust/shift_or_euc_c/LICENSE-MIT
+++ b/third_party/rust/shift_or_euc_c/LICENSE-MIT
@ -1,25 +0,0 @@
-Copyright (c) 2018 Mozilla Foundation
-
-Permission is hereby granted, free of charge, to any
-person obtaining a copy of this software and associated
-documentation files (the "Software"), to deal in the
-Software without restriction, including without
-limitation the rights to use, copy, modify, merge,
-publish, distribute, sublicense, and/or sell copies of
-the Software, and to permit persons to whom the Software
-is furnished to do so, subject to the following
-conditions:
-
-The above copyright notice and this permission notice
-shall be included in all copies or substantial portions
-of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
-ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
-TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
-PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
-SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
-CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
-IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
-DEALINGS IN THE SOFTWARE.
--- a/third_party/rust/shift_or_euc_c/README.md
+++ b/third_party/rust/shift_or_euc_c/README.md
@ -1,13 +0,0 @@
-# shift_or_euc_c
-
-[![Apache 2 / MIT dual-licensed](https://img.shields.io/badge/license-Apache%202%20%2F%20MIT-blue.svg)](https://github.com/hsivonen/shift_or_euc_c/blob/master/COPYRIGHT)
-
-C API for [`shift_or_euc`](https://docs.rs/crate/shift_or_euc).
-
-## Documentation
-
-[API documentation on docs.rs](https://docs.rs/crate/shift_or_euc_c)
-
-## Licensing
-
-See the file named [COPYRIGHT](https://github.com/hsivonen/shift_or_euc_c/blob/master/COPYRIGHT).
--- a/third_party/rust/shift_or_euc_c/include/shift_or_euc.h
+++ b/third_party/rust/shift_or_euc_c/include/shift_or_euc.h
@ -1,88 +0,0 @@
-// Copyright 2018 Mozilla Foundation. See the COPYRIGHT
-// file at the top-level directory of this distribution.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#ifndef shift_or_euc_h
-#define shift_or_euc_h
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#include <stdint.h>
-#include <stdbool.h>
-#include "encoding_rs.h"
-
-#ifndef SHIFT_OR_EUC_DETECTOR
-#define SHIFT_OR_EUC_DETECTOR Detector
-#ifndef __cplusplus
-typedef struct Detector_ Detector;
-#endif
-#endif
-
-/// Instantiates the detector. If `allow_2022` is `true` the possible
-/// guesses are Shift_JIS, EUC-JP, ISO-2022-JP, and undecided. If
-/// `allow_2022` is `false`, the possible guesses are Shift_JIS, EUC-JP,
-/// and undecided.
-///
-/// The instantiated detector must be freed after use using
-/// `shift_or_euc_detector_free`.
-SHIFT_OR_EUC_DETECTOR* shift_or_euc_detector_new(bool allow_2022);
-
-/// Deallocates a detector obtained from `shift_or_euc_detector_new`.
-void shift_or_euc_detector_free(SHIFT_OR_EUC_DETECTOR* detector);
-
-/// Feeds bytes to the detector. If `last` is `true` the end of the stream
-/// is considered to occur immediately after the end of `buffer`.
-/// Otherwise, the stream is expected to continue. `buffer_len` may be zero.
-/// `buffer` must not be `NULL` but may be undereferencable when
-/// `buffer_len` is zero.
-///
-/// If you're running the detector only on a prefix of a complete
-/// document, _do not_ pass `last` as `true` after the prefix if the
-/// stream as a whole still contains more content.
-///
-/// Returns `SHIFT_JIS_ENCODING` if the detector guessed
-/// Shift_JIS. Returns `EUC_JP_ENCODING` if the detector
-/// guessed EUC-JP. Returns `ISO_2022_JP_ENCODING` if the
-/// detector guessed ISO-2022-JP (only possible if `true` was passed as
-/// `allow_2022` when instantiating the detector). Returns `NULL` if the
-/// detector is undecided. If `NULL` is returned even when passing `true`
-/// as `last`, falling back to Shift_JIS is the best guess for Web
-/// purposes.
-///
-/// Do not call again after the function has returned non-`NULL` or after
-/// the function has been called with `true` as `last`.
-///
-/// # Panics
-///
-/// If called after the function has returned non-`NULL` or after the
-/// function has been called with `true` as `last`.
-///
-/// # Undefined Behavior
-///
-/// UB ensues if
-///
-/// * `detector` does not point to a detector obtained from
-///   `shift_or_euc_detector_new` but not yet freed with
-///   `shift_or_euc_detector_free`.
-/// * `buffer` is `NULL`.
-/// * `buffer` and `buffer_len` don't designate a range of memory
-///   valid for reading.
-ENCODING_RS_ENCODING const* shift_or_euc_detector_feed(
-    SHIFT_OR_EUC_DETECTOR* detector,
-    uint8_t const* buffer,
-    size_t buffer_len,
-    bool last
-);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif // shift_or_euc_h
--- a/third_party/rust/shift_or_euc_c/src/lib.rs
+++ b/third_party/rust/shift_or_euc_c/src/lib.rs
@ -1,94 +0,0 @@
-// Copyright 2018 Mozilla Foundation. See the COPYRIGHT
-// file at the top-level directory of this distribution.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#![doc(html_root_url = "https://docs.rs/shift_or_euc_c/0.1.0")]
-
-//! C API for [`shift_or_euc`](https://docs.rs/shift_or_euc/)
-//!
-//! # Panics
-//!
-//! This crate is designed to be used only in a `panic=abort` scenario.
-//! Panic propagation across FFI is not handled!
-//!
-//! # Licensing
-//!
-//! See the file named [COPYRIGHT](https://github.com/hsivonen/shift_or_euc/blob/master/COPYRIGHT).
-
-use encoding_rs::Encoding;
-use shift_or_euc::*;
-
-/// Instantiates the detector. If `allow_2022` is `true` the possible
-/// guesses are Shift_JIS, EUC-JP, ISO-2022-JP, and undecided. If
-/// `allow_2022` is `false`, the possible guesses are Shift_JIS, EUC-JP,
-/// and undecided.
-///
-/// The instantiated detector must be freed after use using
-/// `shift_or_euc_detector_free`.
-#[no_mangle]
-pub unsafe extern "C" fn shift_or_euc_detector_new(allow_2022: bool) -> *mut Detector {
-    Box::into_raw(Box::new(Detector::new(allow_2022)))
-}
-
-/// Deallocates a detector obtained from `shift_or_euc_detector_new`.
-#[no_mangle]
-pub unsafe extern "C" fn shift_or_euc_detector_free(detector: *mut Detector) {
-    let _ = Box::from_raw(detector);
-}
-
-/// Feeds bytes to the detector. If `last` is `true` the end of the stream
-/// is considered to occur immediately after the end of `buffer`.
-/// Otherwise, the stream is expected to continue. `buffer_len` may be zero.
-/// `buffer` must not be `NULL` but may be undereferencable when
-/// `buffer_len` is zero.
-///
-/// If you're running the detector only on a prefix of a complete
-/// document, _do not_ pass `last` as `true` after the prefix if the
-/// stream as a whole still contains more content.
-///
-/// Returns `SHIFT_JIS_ENCODING` if the detector guessed
-/// Shift_JIS. Returns `EUC_JP_ENCODING` if the detector
-/// guessed EUC-JP. Returns `ISO_2022_JP_ENCODING` if the
-/// detector guessed ISO-2022-JP (only possible if `true` was passed as
-/// `allow_2022` when instantiating the detector). Returns `NULL` if the
-/// detector is undecided. If `NULL` is returned even when passing `true`
-/// as `last`, falling back to Shift_JIS is the best guess for Web
-/// purposes.
-///
-/// Do not call again after the function has returned non-`NULL` or after
-/// the function has been called with `true` as `last`.
-///
-/// # Panics
-///
-/// If called after the function has returned non-`NULL` or after the
-/// function has been called with `true` as `last`.
-///
-/// # Undefined Behavior
-///
-/// UB ensues if
-///
-/// * `detector` does not point to a detector obtained from
-///   `shift_or_euc_detector_new` but not yet freed with
-///   `shift_or_euc_detector_free`.
-/// * `buffer` is `NULL`.
-/// * `buffer` and `buffer_len` don't designate a range of memory
-///   valid for reading.
-#[no_mangle]
-pub unsafe extern "C" fn shift_or_euc_detector_feed(
-    detector: *mut Detector,
-    buffer: *const u8,
-    buffer_len: usize,
-    last: bool,
-) -> *const Encoding {
-    if let Some(encoding) = (*detector).feed(::std::slice::from_raw_parts(buffer, buffer_len), last)
-    {
-        encoding
-    } else {
-        ::std::ptr::null()
-    }
-}
--- a/toolkit/actors/ViewSourceChild.jsm
+++ b/toolkit/actors/ViewSourceChild.jsm
@ -52,20 +52,19 @@ class ViewSourceChild extends JSWindowActorChild {
   *        loading.
   */
  viewSource(URL, outerWindowID, lineNumber) {
-    let otherDocShell, forcedCharSet;
+    let otherDocShell;
+    let forceEncodingDetection = false;

    if (outerWindowID) {
      let contentWindow = Services.wm.getOuterWindowWithId(outerWindowID);
      if (contentWindow) {
        otherDocShell = contentWindow.docShell;

-        let utils = contentWindow.windowUtils;
-        let doc = contentWindow.document;
-        forcedCharSet = utils.docCharsetIsForced ? doc.characterSet : null;
+        forceEncodingDetection = contentWindow.windowUtils.docCharsetIsForced;
      }
    }

-    this.loadSource(URL, otherDocShell, lineNumber, forcedCharSet);
+    this.loadSource(URL, otherDocShell, lineNumber, forceEncodingDetection);
  }

  /**
@ -105,18 +104,14 @@ class ViewSourceChild extends JSWindowActorChild {
   * @param lineNumber (optional)
   *        The line number to focus as soon as the source has finished
   *        loading.
-   * @param forcedCharSet (optional)
-   *        The document character set to use instead of the default one.
+   * @param forceEncodingDetection (optional)
+   *        Force autodetection of the character encoding.
   */
-  loadSource(URL, otherDocShell, lineNumber, forcedCharSet) {
+  loadSource(URL, otherDocShell, lineNumber, forceEncodingDetection) {
    const viewSrcURL = "view-source:" + URL;

-    if (forcedCharSet) {
-      try {
-        this.docShell.charset = forcedCharSet;
-      } catch (e) {
-        /* invalid charset */
-      }
+    if (forceEncodingDetection) {
+      this.docShell.forceEncodingDetection();
    }

    ViewSourcePageChild.setInitialLineNumber(lineNumber);
--- a/toolkit/content/widgets/browser-custom-element.js
+++ b/toolkit/content/widgets/browser-custom-element.js
@ -255,8 +255,6 @@

      this._mayEnableCharacterEncodingMenu = null;

-      this._charsetAutodetected = false;
-
      this._contentPrincipal = null;

      this._contentPartitionedPrincipal = null;
@ -585,17 +583,11 @@
        : this.contentDocument.title;
    }

-    set characterSet(val) {
+    forceEncodingDetection() {
      if (this.isRemoteBrowser) {
-        this.sendMessageToActor(
-          "UpdateCharacterSet",
-          { value: val },
-          "BrowserTab"
-        );
-        this._characterSet = val;
+        this.sendMessageToActor("ForceEncodingDetection", {}, "BrowserTab");
      } else {
-        this.docShell.charset = val;
-        this.docShell.gatherCharsetMenuTelemetry();
+        this.docShell.forceEncodingDetection();
      }
    }

@ -615,18 +607,6 @@
      }
    }

-    get charsetAutodetected() {
-      return this.isRemoteBrowser
-        ? this._charsetAutodetected
-        : this.docShell.charsetAutodetected;
-    }
-
-    set charsetAutodetected(aAutodetected) {
-      if (this.isRemoteBrowser) {
-        this._charsetAutodetected = aAutodetected;
-      }
-    }
-
    get contentPrincipal() {
      return this.isRemoteBrowser
        ? this._contentPrincipal
@ -1147,7 +1127,6 @@
      aLocation,
      aCharset,
      aMayEnableCharacterEncodingMenu,
-      aCharsetAutodetected,
      aDocumentURI,
      aTitle,
      aContentPrincipal,
@ -1163,7 +1142,6 @@
        if (aCharset != null) {
          this._characterSet = aCharset;
          this._mayEnableCharacterEncodingMenu = aMayEnableCharacterEncodingMenu;
-          this._charsetAutodetected = aCharsetAutodetected;
        }

        if (aContentType != null) {
@ -1578,7 +1556,6 @@
            "_documentContentType",
            "_characterSet",
            "_mayEnableCharacterEncodingMenu",
-            "_charsetAutodetected",
            "_contentPrincipal",
            "_contentPartitionedPrincipal",
            "_isSyntheticDocument",
--- a/toolkit/library/rust/shared/Cargo.toml
+++ b/toolkit/library/rust/shared/Cargo.toml
@ -39,7 +39,6 @@ cert_storage = { path = "../../../../security/manager/ssl/cert_storage" }
 bitsdownload = { path = "../../../components/bitsdownload", optional = true }
 storage = { path = "../../../../storage/rust" }
 bookmark_sync = { path = "../../../components/places/bookmark_sync", optional = true }
-shift_or_euc_c = "0.1.0"
 chardetng_c = "0.1.1"
 audio_thread_priority = "0.23.4"
 mdns_service = { path="../../../../dom/media/webrtc/transport/mdns_service", optional = true }
--- a/toolkit/library/rust/shared/lib.rs
+++ b/toolkit/library/rust/shared/lib.rs
@ -45,7 +45,6 @@ extern crate processtools;
 #[cfg(feature = "gecko_profiler")]
 extern crate profiler_helper;
 extern crate rsdparsa_capi;
-extern crate shift_or_euc_c;
 extern crate static_prefs;
 extern crate storage;
 #[cfg(feature = "quantum_render")]
--- a/toolkit/locales/en-US/chrome/global/charsetMenu.dtd
+++ b/toolkit/locales/en-US/chrome/global/charsetMenu.dtd
@ -1,5 +0,0 @@
-<!-- This Source Code Form is subject to the terms of the Mozilla Public
-   - License, v. 2.0. If a copy of the MPL was not distributed with this
-   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
-
-<!ENTITY charsetMenu2.label            "Text Encoding">
--- a/toolkit/locales/en-US/chrome/global/charsetMenu.properties
+++ b/toolkit/locales/en-US/chrome/global/charsetMenu.properties
@ -1,114 +0,0 @@
-# This Source Code Form is subject to the terms of the Mozilla Public
-# License, v. 2.0. If a copy of the MPL was not distributed with this
-# file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
-# LOCALIZATION NOTE: The property keys ending with ".key" are for access keys.
-# Localizations may add or delete properties where the property key ends with
-# ".key" as appropriate for the localization. The code that uses this data can
-# deal with the absence of an access key for an item.
-#
-# For gbk, gbk.bis and gbk.bis.key are used to trigger string changes in
-# localizations.
-#
-# In the en-US version of this file, access keys are given to the following:
-# * UTF-8
-# * All encodings that are the fallback encoding for some locale in Firefox
-# * All encodings that are the fallback encoding for some locale in IE
-# * All Japanese encodings
-#
-# For the items whose property key does not end in ".key" and whose value
-# includes "(" U+0028 LEFT PARENTHESIS, the "(" character is significant for
-# processing by CharsetMenu.jsm. If your localization does not use ASCII
-# parentheses where en-US does in this file, please file a bug to make
-# CharsetMenu.jsm also recognize the delimiter your localization uses.
-# (When this code was developed, all localizations appeared to use
-# U+0028 LEFT PARENTHESIS for this purpose.)
-
-# Globally-relevant
-
-_autodetect_all.key =     m
-_autodetect_all     = Automatic
-UTF-8.key        = U
-UTF-8            = Unicode
-windows-1252.key = W
-windows-1252     = Western
-
-# Arabic
-windows-1256.key = A
-windows-1256     = Arabic (Windows)
-ISO-8859-6       = Arabic (ISO)
-
-# Baltic
-windows-1257.key = B
-windows-1257     = Baltic (Windows)
-ISO-8859-4       = Baltic (ISO)
-
-# Central European
-windows-1250.key =         E
-windows-1250     = Central European (Windows)
-ISO-8859-2.key   =       l
-ISO-8859-2       = Central European (ISO)
-
-# Chinese, Simplified
-gbk.bis.key      =          S
-gbk.bis          = Chinese, Simplified
-
-# Chinese, Traditional
-Big5.key         =          T
-Big5             = Chinese, Traditional
-
-# Cyrillic
-windows-1251.key = C
-windows-1251     = Cyrillic (Windows)
-ISO-8859-5       = Cyrillic (ISO)
-KOI8-R           = Cyrillic (KOI8-R)
-KOI8-U           = Cyrillic (KOI8-U)
-IBM866           = Cyrillic (DOS)
-
-# UI string in anticipation of Cyrillic analog of bug 1543077;
-# deliberately not in use yet
-
-# LOCALIZATION NOTE (Cyrillic.key): If taken into use, this string will appear
-# instead of the string for windows-1251.key, so the use of the same
-# accelerator is deliberate.
-Cyrillic.key     = C
-# LOCALIZATION NOTE (Cyrillic): If taken into use, this string will appear
-# as a single item instead of the five items windows-1251, ISO-8859-5,
-# KOI8-R, KOI8-U, and IBM866, so this string does not need to make sense
-# together with those strings and should be translated the way those were
-# but omitting the part in parentheses.
-Cyrillic         = Cyrillic
-
-# Greek
-windows-1253.key = G
-windows-1253     = Greek (Windows)
-ISO-8859-7.key   =          O
-ISO-8859-7       = Greek (ISO)
-
-# Hebrew
-windows-1255.key = H
-windows-1255     = Hebrew
-# LOCALIZATION NOTE (ISO-8859-8): The value for this item should begin with
-# the same word for Hebrew as the value for windows-1255 so that this item
-# sorts right after that one in the collation order for your locale.
-ISO-8859-8       = Hebrew, Visual
-
-# Japanese (NOT AN ENCODING NAME)
-Japanese.key     = J
-Japanese         = Japanese
-
-# Korean
-EUC-KR.key       = K
-EUC-KR           = Korean
-
-# Thai
-windows-874.key  =    i
-windows-874      = Thai
-
-# Turkish
-windows-1254.key =   r
-windows-1254     = Turkish
-
-# Vietnamese
-windows-1258.key = V
-windows-1258     = Vietnamese
--- a/toolkit/locales/jar.mn
+++ b/toolkit/locales/jar.mn
@ -14,8 +14,6 @@
  locale/@AB_CD@/global/autocomplete.properties         (%chrome/global/autocomplete.properties)
  locale/@AB_CD@/global/appPicker.dtd                   (%chrome/global/appPicker.dtd)
  locale/@AB_CD@/global/browser.properties              (%chrome/global/browser.properties)
-  locale/@AB_CD@/global/charsetMenu.dtd                 (%chrome/global/charsetMenu.dtd)
-  locale/@AB_CD@/global/charsetMenu.properties          (%chrome/global/charsetMenu.properties)
  locale/@AB_CD@/global/commonDialog.dtd                (%chrome/global/commonDialog.dtd)
  locale/@AB_CD@/global/commonDialogs.properties        (%chrome/global/commonDialogs.properties)
  locale/@AB_CD@/global/contentAreaCommands.properties  (%chrome/global/contentAreaCommands.properties)
--- a/toolkit/modules/CharsetMenu.jsm
+++ b/toolkit/modules/CharsetMenu.jsm
@ -1,223 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this file,
- * You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-var EXPORTED_SYMBOLS = ["CharsetMenu"];
-
-const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
-const { XPCOMUtils } = ChromeUtils.import(
-  "resource://gre/modules/XPCOMUtils.jsm"
-);
-XPCOMUtils.defineLazyGetter(this, "gBundle", function() {
-  const kUrl = "chrome://global/locale/charsetMenu.properties";
-  return Services.strings.createBundle(kUrl);
-});
-
-ChromeUtils.defineModuleGetter(
-  this,
-  "Deprecated",
-  "resource://gre/modules/Deprecated.jsm"
-);
-
-/**
- * This set contains encodings that are in the Encoding Standard, except:
- *  - Japanese encodings are represented by one autodetection item
- *  - x-user-defined, which practically never makes sense as an end-user-chosen
- *    override.
- *  - Encodings that IE11 doesn't have in its corresponding menu.
- */
-const kEncodings = new Set([
-  // Globally relevant
-  "_autodetect_all", // (NOT AN ENCODING NAME; using IE-consistent magic name)
-  "UTF-8",
-  "windows-1252",
-  // Arabic
-  "windows-1256",
-  "ISO-8859-6",
-  // Baltic
-  "windows-1257",
-  "ISO-8859-4",
-  // "ISO-8859-13", // Hidden since not in menu in IE11
-  // Central European
-  "windows-1250",
-  "ISO-8859-2",
-  // Chinese, Simplified
-  "GBK",
-  // Chinese, Traditional
-  "Big5",
-  // Cyrillic
-  "windows-1251",
-  "ISO-8859-5",
-  "KOI8-R",
-  "KOI8-U",
-  "IBM866", // Not in menu in Chromium. Maybe drop this?
-  // "x-mac-cyrillic", // Not in menu in IE11 or Chromium.
-  // Greek
-  "windows-1253",
-  "ISO-8859-7",
-  // Hebrew
-  "windows-1255",
-  "ISO-8859-8",
-  // Japanese (NOT AN ENCODING NAME)
-  "Japanese",
-  // Korean
-  "EUC-KR",
-  // Thai
-  "windows-874",
-  // Turkish
-  "windows-1254",
-  // Vietnamese
-  "windows-1258",
-  // Hiding rare European encodings that aren't in the menu in IE11 and would
-  // make the menu messy by sorting all over the place
-  // "ISO-8859-3",
-  // "ISO-8859-10",
-  // "ISO-8859-14",
-  // "ISO-8859-15",
-  // "ISO-8859-16",
-  // "macintosh"
-]);
-
-// Always at the start of the menu, in this order, followed by a separator.
-const kPinned = ["_autodetect_all", "UTF-8", "windows-1252"];
-
-kPinned.forEach(x => kEncodings.delete(x));
-
-function CharsetComparator(a, b) {
-  // Normal sorting sorts the part in parenthesis in an order that
-  // happens to make the less frequently-used items first.
-  let titleA = a.label.replace(/\(.*/, "") + b.value;
-  let titleB = b.label.replace(/\(.*/, "") + a.value;
-  // Secondarily reverse sort by encoding name to sort "windows"
-  return titleA.localeCompare(titleB) || b.value.localeCompare(a.value);
-}
-
-var gCharsetInfoCache, gPinnedInfoCache;
-
-var CharsetMenu = {
-  build(parent, deprecatedShowAccessKeys = true) {
-    if (!deprecatedShowAccessKeys) {
-      Deprecated.warning(
-        "CharsetMenu no longer supports building a menu with no access keys.",
-        "https://bugzilla.mozilla.org/show_bug.cgi?id=1088710"
-      );
-    }
-    function createDOMNode(doc, nodeInfo) {
-      let node = doc.createXULElement("menuitem");
-      node.setAttribute("type", "radio");
-      node.setAttribute("name", nodeInfo.name + "Group");
-      node.setAttribute(nodeInfo.name, nodeInfo.value);
-      node.setAttribute("label", nodeInfo.label);
-      if (nodeInfo.accesskey) {
-        node.setAttribute("accesskey", nodeInfo.accesskey);
-      }
-      return node;
-    }
-
-    if (parent.hasChildNodes()) {
-      // Charset menu already built
-      return;
-    }
-    this._ensureDataReady();
-    let doc = parent.ownerDocument;
-
-    gPinnedInfoCache.forEach(charsetInfo =>
-      parent.appendChild(createDOMNode(doc, charsetInfo))
-    );
-    parent.appendChild(doc.createXULElement("menuseparator"));
-    gCharsetInfoCache.forEach(charsetInfo =>
-      parent.appendChild(createDOMNode(doc, charsetInfo))
-    );
-  },
-
-  getData() {
-    this._ensureDataReady();
-    return {
-      pinnedCharsets: gPinnedInfoCache,
-      otherCharsets: gCharsetInfoCache,
-    };
-  },
-
-  _ensureDataReady() {
-    if (!gCharsetInfoCache) {
-      gPinnedInfoCache = this.getCharsetInfo(kPinned, false);
-      gCharsetInfoCache = this.getCharsetInfo(kEncodings);
-    }
-  },
-
-  getCharsetInfo(charsets, sort = true) {
-    let list = Array.from(charsets, charset => ({
-      label: this._getCharsetLabel(charset),
-      accesskey: this._getCharsetAccessKey(charset),
-      name: "charset",
-      value: charset,
-    }));
-
-    if (sort) {
-      list.sort(CharsetComparator);
-    }
-    return list;
-  },
-
-  _getCharsetLabel(charset) {
-    if (charset == "GBK") {
-      // Localization key has been revised
-      charset = "gbk.bis";
-    }
-    try {
-      return gBundle.GetStringFromName(charset);
-    } catch (ex) {}
-    return charset;
-  },
-  _getCharsetAccessKey(charset) {
-    if (charset == "GBK") {
-      // Localization key has been revised
-      charset = "gbk.bis";
-    }
-    try {
-      return gBundle.GetStringFromName(charset + ".key");
-    } catch (ex) {}
-    return "";
-  },
-
-  /**
-   * For substantially similar encodings, treat two encodings as the same
-   * for the purpose of the check mark.
-   */
-  foldCharset(charset, isAutodetected) {
-    if (isAutodetected) {
-      switch (charset) {
-        case "Shift_JIS":
-        case "EUC-JP":
-        case "ISO-2022-JP":
-          return "Japanese";
-        default:
-        // fall through
-      }
-    }
-    switch (charset) {
-      case "ISO-8859-8-I":
-        return "windows-1255";
-
-      case "gb18030":
-        return "GBK";
-
-      default:
-        return charset;
-    }
-  },
-
-  /**
-   * This method is for comm-central callers only.
-   */
-  update(parent, charset) {
-    let menuitem = parent
-      .getElementsByAttribute("charset", this.foldCharset(charset, false))
-      .item(0);
-    if (menuitem) {
-      menuitem.setAttribute("checked", "true");
-    }
-  },
-};
-
-Object.freeze(CharsetMenu);
--- a/toolkit/modules/moz.build
+++ b/toolkit/modules/moz.build
@ -48,9 +48,6 @@ with Files("tests/xpcshell/test_UpdateUtils*.js"):
 with Files("AsyncPrefs.jsm"):
    BUG_COMPONENT = ("Core", "Security: Process Sandboxing")

-with Files("CharsetMenu.jsm"):
-    BUG_COMPONENT = ("Firefox", "Toolbars and Customization")
-
 with Files("Color.jsm"):
    BUG_COMPONENT = ("Toolkit", "Find Toolbar")

@ -160,7 +157,6 @@ EXTRA_JS_MODULES += [
    "BrowserUtils.jsm",
    "CanonicalJSON.jsm",
    "CertUtils.jsm",
-    "CharsetMenu.jsm",
    "Color.jsm",
    "Console.jsm",
    "ContentDOMReference.jsm",
				`@ -1 +0,0 @@`
				{"files":{"CONTRIBUTING.md":"0e64fb3dd5a00e3fd528de6442de3f2ca851bd718c45cca0871aaf4eedac9ee1","COPYRIGHT":"3a7313aa2f19bf7095a2fd731c3d5e76f38d5e4640bd2a115d53032f24b2aa6c","Cargo.toml":"f9f41b76ecbe257a312ab09ed1208189b8dc9952d12d17a216fe2846d1d471c8","LICENSE-APACHE":"cfc7749b96f63bd31c3c42b5c471bf756814053e847c10f3eb003417bc523d30","LICENSE-MIT":"dac4dde23582d18b01701032860d8f8a1979fb2cf626060ca8de77e081a2a3d5","README.md":"b7148745a7ef59788e76fbe638d4b41c54dcaa1313a809f4630a020645f892a8","examples/detect.rs":"eb7239ccc802290ef24331db600ca1226198801dd86df86876b4b738ef4b8470","src/lib.rs":"f2a83db125d553af5c6fabae0487ef211aad62f2d93c4418dc510cbd425d472a"},"package":"f930dea4685b9803954b9d74cdc175c6d946a22f2eafe5aa2e9a58cdcae7da8c"}