diff --git a/browser/devtools/debugger/debugger-controller.js b/browser/devtools/debugger/debugger-controller.js
index 67ae3c9402f9..2e742074fb7f 100644
--- a/browser/devtools/debugger/debugger-controller.js
+++ b/browser/devtools/debugger/debugger-controller.js
@@ -423,6 +423,7 @@ function StackFrames() {
   this._onResumed = this._onResumed.bind(this);
   this._onFrames = this._onFrames.bind(this);
   this._onFramesCleared = this._onFramesCleared.bind(this);
+  this._onBlackBoxChange = this._onBlackBoxChange.bind(this);
   this._afterFramesCleared = this._afterFramesCleared.bind(this);
   this.evaluate = this.evaluate.bind(this);
 }
@@ -447,6 +448,7 @@ StackFrames.prototype = {
     this.activeThread.addListener("resumed", this._onResumed);
     this.activeThread.addListener("framesadded", this._onFrames);
     this.activeThread.addListener("framescleared", this._onFramesCleared);
+    window.addEventListener("Debugger:BlackBoxChange", this._onBlackBoxChange, false);
     this._handleTabNavigation();
   },
 
@@ -462,6 +464,7 @@ StackFrames.prototype = {
     this.activeThread.removeListener("resumed", this._onResumed);
     this.activeThread.removeListener("framesadded", this._onFrames);
     this.activeThread.removeListener("framescleared", this._onFramesCleared);
+    window.removeEventListener("Debugger:BlackBoxChange", this._onBlackBoxChange, false);
   },
 
   /**
@@ -594,12 +597,22 @@ StackFrames.prototype = {
     // Make sure all the previous stackframes are removed before re-adding them.
     DebuggerView.StackFrames.empty();
 
+    let previousBlackBoxed = null;
     for (let frame of this.activeThread.cachedFrames) {
-      let { depth, where: { url, line } } = frame;
+      let { depth, where: { url, line }, isBlackBoxed } = frame;
       let frameLocation = NetworkHelper.convertToUnicode(unescape(url));
       let frameTitle = StackFrameUtils.getFrameTitle(frame);
 
-      DebuggerView.StackFrames.addFrame(frameTitle, frameLocation, line, depth);
+      if (isBlackBoxed) {
+        if (previousBlackBoxed == url) {
+          continue;
+        }
+        previousBlackBoxed = url;
+      } else {
+        previousBlackBoxed = null;
+      }
+
+      DebuggerView.StackFrames.addFrame(frameTitle, frameLocation, line, depth, isBlackBoxed);
     }
     if (this.currentFrame == null) {
       DebuggerView.StackFrames.selectedDepth = 0;
@@ -626,6 +639,18 @@ StackFrames.prototype = {
     window.setTimeout(this._afterFramesCleared, FRAME_STEP_CLEAR_DELAY);
   },
 
+  /**
+   * Handler for the debugger's BlackBoxChange notification.
+   */
+  _onBlackBoxChange: function() {
+    if (this.activeThread.state == "paused") {
+      // We have to clear out the existing frames and refetch them to get their
+      // updated black boxed status.
+      this.activeThread._clearFrames();
+      this.activeThread.fillFrames(CALL_STACK_PAGE_SIZE);
+    }
+  },
+
   /**
    * Called soon after the thread client's framescleared notification.
    */
@@ -1000,6 +1025,27 @@ SourceScripts.prototype = {
     window.dispatchEvent(document, "Debugger:AfterSourcesAdded");
   },
 
+  /**
+   * Set the black boxed status of the given source.
+   *
+   * @param Object aSource
+   *        The source form.
+   * @param bool aBlackBoxFlag
+   *        True to black box the source, false to un-black box it.
+   */
+  blackBox: function(aSource, aBlackBoxFlag) {
+    const sourceClient = this.activeThread.source(aSource);
+    sourceClient[aBlackBoxFlag ? "blackBox" : "unblackBox"](function({ error, message }) {
+      if (error) {
+        let msg = "Could not toggle black boxing for "
+          + aSource.url + ": " + message;
+        dumpn(msg);
+        return void Cu.reportError(msg);
+      }
+      window.dispatchEvent(document, "Debugger:BlackBoxChange", sourceClient);
+    });
+  },
+
   /**
    * Gets a specified source's text.
    *
diff --git a/browser/devtools/debugger/debugger-panes.js b/browser/devtools/debugger/debugger-panes.js
index 8f1c934f609a..29491fc1b8b5 100644
--- a/browser/devtools/debugger/debugger-panes.js
+++ b/browser/devtools/debugger/debugger-panes.js
@@ -18,6 +18,7 @@ function SourcesView() {
   this._onSourceSelect = this._onSourceSelect.bind(this);
   this._onSourceClick = this._onSourceClick.bind(this);
   this._onBreakpointRemoved = this._onBreakpointRemoved.bind(this);
+  this._onSourceCheck = this._onSourceCheck.bind(this);
   this._onBreakpointClick = this._onBreakpointClick.bind(this);
   this._onBreakpointCheckboxClick = this._onBreakpointCheckboxClick.bind(this);
   this._onConditionalPopupShowing = this._onConditionalPopupShowing.bind(this);
@@ -34,9 +35,12 @@ SourcesView.prototype = Heritage.extend(WidgetMethods, {
   initialize: function() {
     dumpn("Initializing the SourcesView");
 
-    this.widget = new SideMenuWidget(document.getElementById("sources"));
+    this.widget = new SideMenuWidget(document.getElementById("sources"), {
+      showCheckboxes: true
+    });
     this.emptyText = L10N.getStr("noSourcesText");
     this.unavailableText = L10N.getStr("noMatchingSourcesText");
+    this._blackBoxCheckboxTooltip = L10N.getStr("blackBoxCheckboxTooltip");
 
     this._commandset = document.getElementById("debuggerCommands");
     this._popupset = document.getElementById("debuggerPopupset");
@@ -48,6 +52,7 @@ SourcesView.prototype = Heritage.extend(WidgetMethods, {
     window.addEventListener("Debugger:EditorUnloaded", this._onEditorUnload, false);
     this.widget.addEventListener("select", this._onSourceSelect, false);
     this.widget.addEventListener("click", this._onSourceClick, false);
+    this.widget.addEventListener("check", this._onSourceCheck, false);
     this._cbPanel.addEventListener("popupshowing", this._onConditionalPopupShowing, false);
     this._cbPanel.addEventListener("popupshown", this._onConditionalPopupShown, false);
     this._cbPanel.addEventListener("popuphiding", this._onConditionalPopupHiding, false);
@@ -70,6 +75,7 @@ SourcesView.prototype = Heritage.extend(WidgetMethods, {
     window.removeEventListener("Debugger:EditorUnloaded", this._onEditorUnload, false);
     this.widget.removeEventListener("select", this._onSourceSelect, false);
     this.widget.removeEventListener("click", this._onSourceClick, false);
+    this.widget.removeEventListener("check", this._onSourceCheck, false);
     this._cbPanel.removeEventListener("popupshowing", this._onConditionalPopupShowing, false);
     this._cbPanel.removeEventListener("popupshowing", this._onConditionalPopupShown, false);
     this._cbPanel.removeEventListener("popuphiding", this._onConditionalPopupHiding, false);
@@ -109,6 +115,8 @@ SourcesView.prototype = Heritage.extend(WidgetMethods, {
     this.push([label, url, group], {
       staged: aOptions.staged, /* stage the item to be appended later? */
       attachment: {
+        checkboxState: !aSource.isBlackBoxed,
+        checkboxTooltip: this._blackBoxCheckboxTooltip,
         source: aSource
       }
     });
@@ -639,6 +647,14 @@ SourcesView.prototype = Heritage.extend(WidgetMethods, {
     DebuggerView.Filtering.target = this;
   },
 
+  /**
+   * The check listener for the sources container.
+   */
+  _onSourceCheck: function({ detail: { checked }, target }) {
+    let item = this.getItemForElement(target);
+    DebuggerController.SourceScripts.blackBox(item.attachment.source, !checked);
+  },
+
   /**
    * The click listener for a breakpoint container.
    */
diff --git a/browser/devtools/debugger/debugger-toolbar.js b/browser/devtools/debugger/debugger-toolbar.js
index 76d484f468af..6caccf6a8ae4 100644
--- a/browser/devtools/debugger/debugger-toolbar.js
+++ b/browser/devtools/debugger/debugger-toolbar.js
@@ -424,8 +424,10 @@ StackFramesView.prototype = Heritage.extend(WidgetMethods, {
    *        The line number to be displayed in the list.
    * @param number aDepth
    *        The frame depth specified by the debugger.
+   * @param boolean aIsBlackBoxed
+   *        Whether or not the frame is black boxed.
    */
-  addFrame: function(aFrameTitle, aSourceLocation, aLineNumber, aDepth) {
+  addFrame: function(aFrameTitle, aSourceLocation, aLineNumber, aDepth, aIsBlackBoxed) {
     // Create the element node and menu entry for the stack frame item.
     let frameView = this._createFrameView.apply(this, arguments);
     let menuEntry = this._createMenuEntry.apply(this, arguments);
@@ -471,29 +473,35 @@ StackFramesView.prototype = Heritage.extend(WidgetMethods, {
    *        The line number to be displayed in the list.
    * @param number aDepth
    *        The frame depth specified by the debugger.
+   * @param boolean aIsBlackBoxed
+   *        Whether or not the frame is black boxed.
    * @return nsIDOMNode
    *         The stack frame view.
    */
-  _createFrameView: function(aFrameTitle, aSourceLocation, aLineNumber, aDepth) {
-    let frameDetails =
-      SourceUtils.trimUrlLength(
-        SourceUtils.getSourceLabel(aSourceLocation),
-        STACK_FRAMES_SOURCE_URL_MAX_LENGTH,
-        STACK_FRAMES_SOURCE_URL_TRIM_SECTION) + SEARCH_LINE_FLAG + aLineNumber;
-
-    let frameTitleNode = document.createElement("label");
-    frameTitleNode.className = "plain dbg-stackframe-title breadcrumbs-widget-item-tag";
-    frameTitleNode.setAttribute("value", aFrameTitle);
-
-    let frameDetailsNode = document.createElement("label");
-    frameDetailsNode.className = "plain dbg-stackframe-details breadcrumbs-widget-item-id";
-    frameDetailsNode.setAttribute("value", frameDetails);
-
+  _createFrameView: function(aFrameTitle, aSourceLocation, aLineNumber, aDepth, aIsBlackBoxed) {
     let container = document.createElement("hbox");
     container.id = "stackframe-" + aDepth;
     container.className = "dbg-stackframe";
 
-    container.appendChild(frameTitleNode);
+    let frameDetails = SourceUtils.trimUrlLength(
+      SourceUtils.getSourceLabel(aSourceLocation),
+      STACK_FRAMES_SOURCE_URL_MAX_LENGTH,
+      STACK_FRAMES_SOURCE_URL_TRIM_SECTION);
+
+    if (aIsBlackBoxed) {
+      container.classList.add("dbg-stackframe-black-boxed");
+    } else {
+      let frameTitleNode = document.createElement("label");
+      frameTitleNode.className = "plain dbg-stackframe-title breadcrumbs-widget-item-tag";
+      frameTitleNode.setAttribute("value", aFrameTitle);
+      container.appendChild(frameTitleNode);
+
+      frameDetails += SEARCH_LINE_FLAG + aLineNumber;
+    }
+
+    let frameDetailsNode = document.createElement("label");
+    frameDetailsNode.className = "plain dbg-stackframe-details breadcrumbs-widget-item-id";
+    frameDetailsNode.setAttribute("value", frameDetails);
     container.appendChild(frameDetailsNode);
 
     return container;
@@ -510,10 +518,12 @@ StackFramesView.prototype = Heritage.extend(WidgetMethods, {
    *        The line number to be displayed in the list.
    * @param number aDepth
    *        The frame depth specified by the debugger.
+   * @param boolean aIsBlackBoxed
+   *        Whether or not the frame is black boxed.
    * @return object
    *         An object containing the stack frame command and menu item.
    */
-  _createMenuEntry: function(aFrameTitle, aSourceLocation, aLineNumber, aDepth) {
+  _createMenuEntry: function(aFrameTitle, aSourceLocation, aLineNumber, aDepth, aIsBlackBoxed) {
     let frameDescription =
       SourceUtils.trimUrlLength(
         SourceUtils.getSourceLabel(aSourceLocation),
diff --git a/browser/devtools/debugger/test/Makefile.in b/browser/devtools/debugger/test/Makefile.in
index 1bac0850c439..d05e9a263dca 100644
--- a/browser/devtools/debugger/test/Makefile.in
+++ b/browser/devtools/debugger/test/Makefile.in
@@ -12,6 +12,10 @@ include $(DEPTH)/config/autoconf.mk
 
 MOCHITEST_BROWSER_TESTS = \
 	browser_dbg_aaa_run_first_leaktest.js \
+	browser_dbg_blackboxing-01.js \
+	browser_dbg_blackboxing-02.js \
+	browser_dbg_blackboxing-03.js \
+	browser_dbg_blackboxing-04.js \
 	browser_dbg_clean-exit.js \
 	browser_dbg_cmd.js \
 	browser_dbg_cmd_break.js \
@@ -112,6 +116,11 @@ MOCHITEST_BROWSER_TESTS = \
 	$(NULL)
 
 MOCHITEST_BROWSER_PAGES = \
+	browser_dbg_blackboxing.html \
+	blackboxing_blackboxme.js \
+	blackboxing_one.js \
+	blackboxing_two.js \
+	blackboxing_three.js \
 	browser_dbg_cmd_break.html \
 	browser_dbg_cmd.html \
 	testactors.js \
diff --git a/browser/devtools/debugger/test/blackboxing_blackboxme.js b/browser/devtools/debugger/test/blackboxing_blackboxme.js
new file mode 100644
index 000000000000..713b3d50d89d
--- /dev/null
+++ b/browser/devtools/debugger/test/blackboxing_blackboxme.js
@@ -0,0 +1,9 @@
+function blackboxme(fn) {
+  (function one() {
+    (function two() {
+      (function three() {
+        fn();
+      }());
+    }());
+  }());
+}
diff --git a/browser/devtools/debugger/test/blackboxing_one.js b/browser/devtools/debugger/test/blackboxing_one.js
new file mode 100644
index 000000000000..ca366e9166d8
--- /dev/null
+++ b/browser/devtools/debugger/test/blackboxing_one.js
@@ -0,0 +1 @@
+function one() { two(); }
diff --git a/browser/devtools/debugger/test/blackboxing_three.js b/browser/devtools/debugger/test/blackboxing_three.js
new file mode 100644
index 000000000000..466acf18f4c6
--- /dev/null
+++ b/browser/devtools/debugger/test/blackboxing_three.js
@@ -0,0 +1 @@
+function three() { doDebuggerStatement(); }
diff --git a/browser/devtools/debugger/test/blackboxing_two.js b/browser/devtools/debugger/test/blackboxing_two.js
new file mode 100644
index 000000000000..9931515fc6de
--- /dev/null
+++ b/browser/devtools/debugger/test/blackboxing_two.js
@@ -0,0 +1 @@
+function two() { three(); }
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-01.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-01.js
new file mode 100644
index 000000000000..e5bec3d87c0a
--- /dev/null
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-01.js
@@ -0,0 +1,76 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Test that if we black box a source and then refresh, it is still black boxed.
+ */
+
+const TAB_URL = EXAMPLE_URL + "binary_search.html";
+
+var gPane = null;
+var gTab = null;
+var gDebuggee = null;
+var gDebugger = null;
+
+function test()
+{
+  let scriptShown = false;
+  let framesAdded = false;
+  let resumed = false;
+  let testStarted = false;
+
+  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
+    resumed = true;
+    gTab = aTab;
+    gDebuggee = aDebuggee;
+    gPane = aPane;
+    gDebugger = gPane.panelWin;
+
+    testBlackBoxSource();
+  });
+}
+
+function testBlackBoxSource() {
+  once(gDebugger, "Debugger:SourceShown", function () {
+    const checkbox = gDebugger.document.querySelector(".side-menu-widget-item-checkbox");
+    ok(checkbox, "Should get the checkbox for black boxing the source");
+    ok(checkbox.checked, "Should not be black boxed by default");
+
+    once(gDebugger, "Debugger:BlackBoxChange", function (event) {
+      const sourceClient = event.detail;
+      ok(sourceClient.isBlackBoxed, "The source should be black boxed now");
+      ok(!checkbox.checked, "The checkbox should no longer be checked.");
+
+      testBlackBoxReload();
+    });
+
+    checkbox.click();
+  });
+}
+
+function testBlackBoxReload() {
+  once(gDebugger, "Debugger:SourceShown", function () {
+    const checkbox = gDebugger.document.querySelector(".side-menu-widget-item-checkbox");
+    ok(checkbox, "Should get the checkbox for black boxing the source");
+    ok(!checkbox.checked, "Should still be black boxed");
+
+    closeDebuggerAndFinish();
+  });
+
+  gDebuggee.location.reload();
+}
+
+function once(target, event, callback) {
+  target.addEventListener(event, function _listener(...args) {
+    target.removeEventListener(event, _listener, false);
+    callback.apply(null, args);
+  }, false);
+}
+
+registerCleanupFunction(function() {
+  removeTab(gTab);
+  gPane = null;
+  gTab = null;
+  gDebuggee = null;
+  gDebugger = null;
+});
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-02.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-02.js
new file mode 100644
index 000000000000..1be7d49115f3
--- /dev/null
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-02.js
@@ -0,0 +1,87 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Test that black boxed frames are compressed into a single frame on the stack
+ * view.
+ */
+
+const TAB_URL = EXAMPLE_URL + "browser_dbg_blackboxing.html";
+const BLACKBOXME_URL = EXAMPLE_URL + "blackboxing_blackboxme.js"
+
+var gPane = null;
+var gTab = null;
+var gDebuggee = null;
+var gDebugger = null;
+
+function test()
+{
+  let scriptShown = false;
+  let framesAdded = false;
+  let resumed = false;
+  let testStarted = false;
+
+  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
+    resumed = true;
+    gTab = aTab;
+    gDebuggee = aDebuggee;
+    gPane = aPane;
+    gDebugger = gPane.panelWin;
+
+    testBlackBoxSource();
+  });
+}
+
+function testBlackBoxSource() {
+  once(gDebugger, "Debugger:SourceShown", function () {
+    const checkbox = getBlackBoxCheckbox(BLACKBOXME_URL);
+    ok(checkbox, "Should get the checkbox for blackBoxing the source");
+
+    once(gDebugger, "Debugger:BlackBoxChange", function (event) {
+      const sourceClient = event.detail;
+      ok(sourceClient.isBlackBoxed, "The source should be black boxed now");
+
+      testBlackBoxStack();
+    });
+
+    checkbox.click();
+  });
+}
+
+function testBlackBoxStack() {
+  const { activeThread } = gDebugger.DebuggerController;
+  activeThread.addOneTimeListener("framesadded", function () {
+    const frames = gDebugger.DebuggerView.StackFrames.widget._list;
+
+    is(frames.querySelectorAll(".dbg-stackframe").length, 3,
+       "Should only get 3 frames");
+
+    is(frames.querySelectorAll(".dbg-stackframe-black-boxed").length, 1,
+       "And one of them should be the combined black boxed frames");
+
+    closeDebuggerAndFinish();
+  });
+
+  gDebuggee.runTest();
+}
+
+function getBlackBoxCheckbox(url) {
+  return gDebugger.document.querySelector(
+    ".side-menu-widget-item[tooltiptext=\""
+      + url + "\"] .side-menu-widget-item-checkbox");
+}
+
+function once(target, event, callback) {
+  target.addEventListener(event, function _listener(...args) {
+    target.removeEventListener(event, _listener, false);
+    callback.apply(null, args);
+  }, false);
+}
+
+registerCleanupFunction(function() {
+  removeTab(gTab);
+  gPane = null;
+  gTab = null;
+  gDebuggee = null;
+  gDebugger = null;
+});
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-03.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-03.js
new file mode 100644
index 000000000000..5f0cae2876ef
--- /dev/null
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-03.js
@@ -0,0 +1,96 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Test that black boxed frames are compressed into a single frame on the stack
+ * view when we are already paused.
+ */
+
+const TAB_URL = EXAMPLE_URL + "browser_dbg_blackboxing.html";
+const BLACKBOXME_URL = EXAMPLE_URL + "blackboxing_blackboxme.js"
+
+var gPane = null;
+var gTab = null;
+var gDebuggee = null;
+var gDebugger = null;
+
+function test()
+{
+  let scriptShown = false;
+  let framesAdded = false;
+  let resumed = false;
+  let testStarted = false;
+
+  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
+    resumed = true;
+    gTab = aTab;
+    gDebuggee = aDebuggee;
+    gPane = aPane;
+    gDebugger = gPane.panelWin;
+
+    once(gDebugger, "Debugger:SourceShown", function () {
+      testBlackBoxStack();
+    });
+  });
+}
+
+function testBlackBoxStack() {
+  const { activeThread } = gDebugger.DebuggerController;
+  activeThread.addOneTimeListener("framesadded", function () {
+    const frames = gDebugger.DebuggerView.StackFrames.widget._list;
+
+    is(frames.querySelectorAll(".dbg-stackframe").length, 6,
+       "Should get 6 frames");
+
+    is(frames.querySelectorAll(".dbg-stackframe-black-boxed").length, 0,
+       "And none of them are black boxed");
+
+    testBlackBoxSource();
+  });
+
+  gDebuggee.runTest();
+}
+
+function testBlackBoxSource() {
+  const checkbox = getBlackBoxCheckbox(BLACKBOXME_URL);
+  ok(checkbox, "Should get the checkbox for black boxing the source");
+
+  once(gDebugger, "Debugger:BlackBoxChange", function (event) {
+    const { activeThread } = gDebugger.DebuggerController;
+    activeThread.addOneTimeListener("framesadded", function () {
+      const sourceClient = event.detail;
+      ok(sourceClient.isBlackBoxed, "The source should be black boxed now");
+
+      const frames = gDebugger.DebuggerView.StackFrames.widget._list;
+      is(frames.querySelectorAll(".dbg-stackframe").length, 3,
+         "Should only get 3 frames");
+      is(frames.querySelectorAll(".dbg-stackframe-black-boxed").length, 1,
+         "And one of them is the combined black boxed frames");
+
+      closeDebuggerAndFinish();
+    });
+  });
+
+  checkbox.click();
+}
+
+function getBlackBoxCheckbox(url) {
+  return gDebugger.document.querySelector(
+    ".side-menu-widget-item[tooltiptext=\""
+      + url + "\"] .side-menu-widget-item-checkbox");
+}
+
+function once(target, event, callback) {
+  target.addEventListener(event, function _listener(...args) {
+    target.removeEventListener(event, _listener, false);
+    callback.apply(null, args);
+  }, false);
+}
+
+registerCleanupFunction(function() {
+  removeTab(gTab);
+  gPane = null;
+  gTab = null;
+  gDebuggee = null;
+  gDebugger = null;
+});
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing-04.js b/browser/devtools/debugger/test/browser_dbg_blackboxing-04.js
new file mode 100644
index 000000000000..f09ce6ffa071
--- /dev/null
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing-04.js
@@ -0,0 +1,84 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Test that we get a stack frame for each black boxed source, not a single one
+ * for all of them.
+ */
+
+const TAB_URL = EXAMPLE_URL + "browser_dbg_blackboxing.html";
+
+var gPane = null;
+var gTab = null;
+var gDebuggee = null;
+var gDebugger = null;
+
+function test()
+{
+  let scriptShown = false;
+  let framesAdded = false;
+  let resumed = false;
+  let testStarted = false;
+
+  debug_tab_pane(TAB_URL, function(aTab, aDebuggee, aPane) {
+    resumed = true;
+    gTab = aTab;
+    gDebuggee = aDebuggee;
+    gPane = aPane;
+    gDebugger = gPane.panelWin;
+
+    once(gDebugger, "Debugger:SourceShown", function () {
+      blackBoxSources();
+    });
+  });
+}
+
+function blackBoxSources() {
+  let timesFired = 0;
+  gDebugger.addEventListener("Debugger:BlackBoxChange", function _onBlackboxChange() {
+    if (++timesFired !== 3) {
+      return;
+    }
+    gDebugger.removeEventListener("Debugger:BlackBoxChange", _onBlackboxChange, false);
+
+    const { activeThread } = gDebugger.DebuggerController;
+    activeThread.addOneTimeListener("framesadded", testStackFrames);
+
+    gDebuggee.one();
+  }, false);
+
+  getBlackBoxCheckbox(EXAMPLE_URL + "blackboxing_one.js").click();
+  getBlackBoxCheckbox(EXAMPLE_URL + "blackboxing_two.js").click();
+  getBlackBoxCheckbox(EXAMPLE_URL + "blackboxing_three.js").click();
+}
+
+function testStackFrames() {
+  const frames = gDebugger.DebuggerView.StackFrames.widget._list;
+  is(frames.querySelectorAll(".dbg-stackframe").length, 4,
+     "Should get 4 frames (one -> two -> three -> doDebuggerStatement)");
+  is(frames.querySelectorAll(".dbg-stackframe-black-boxed").length, 3,
+     "And one, two, and three should each have their own black boxed frame.");
+
+  closeDebuggerAndFinish();
+}
+
+function getBlackBoxCheckbox(url) {
+  return gDebugger.document.querySelector(
+    ".side-menu-widget-item[tooltiptext=\""
+      + url + "\"] .side-menu-widget-item-checkbox");
+}
+
+function once(target, event, callback) {
+  target.addEventListener(event, function _listener(...args) {
+    target.removeEventListener(event, _listener, false);
+    callback.apply(null, args);
+  }, false);
+}
+
+registerCleanupFunction(function() {
+  removeTab(gTab);
+  gPane = null;
+  gTab = null;
+  gDebuggee = null;
+  gDebugger = null;
+});
diff --git a/browser/devtools/debugger/test/browser_dbg_blackboxing.html b/browser/devtools/debugger/test/browser_dbg_blackboxing.html
new file mode 100644
index 000000000000..a4154b001525
--- /dev/null
+++ b/browser/devtools/debugger/test/browser_dbg_blackboxing.html
@@ -0,0 +1,23 @@
+<!DOCTYPE HTML>
+<html>
+  <head>
+    <meta charset='utf-8'/>
+    <title>Browser Debugger Blackbox Test</title>
+    <!-- Any copyright is dedicated to the Public Domain.
+         http://creativecommons.org/publicdomain/zero/1.0/ -->
+    <script type="text/javascript" src="blackboxing_blackboxme.js"></script>
+    <script type="text/javascript" src="blackboxing_one.js"></script>
+    <script type="text/javascript" src="blackboxing_two.js"></script>
+    <script type="text/javascript" src="blackboxing_three.js"></script>
+    <script>
+      function runTest() {
+        blackboxme(doDebuggerStatement);
+      }
+      function doDebuggerStatement() {
+        debugger;
+      }
+    </script>
+  </head>
+  <body>
+  </body>
+</html>
diff --git a/browser/devtools/shared/widgets/SideMenuWidget.jsm b/browser/devtools/shared/widgets/SideMenuWidget.jsm
index d4ca8d9f0d41..f24f0fe78226 100644
--- a/browser/devtools/shared/widgets/SideMenuWidget.jsm
+++ b/browser/devtools/shared/widgets/SideMenuWidget.jsm
@@ -25,21 +25,28 @@ this.EXPORTED_SYMBOLS = ["SideMenuWidget"];
  *
  * @param nsIDOMNode aNode
  *        The element associated with the widget.
- * @param boolean aShowArrows
- *        Specifies if items in this container should display horizontal arrows.
+ * @param Object aOptions
+ *        - showArrows: Specifies if items in this container should display
+ *          horizontal arrows.
+ *        - showCheckboxes: Specifies if items in this container should display
+ *          checkboxes.
  */
-this.SideMenuWidget = function SideMenuWidget(aNode, aShowArrows = true) {
+this.SideMenuWidget = function SideMenuWidget(aNode, aOptions={}) {
   this.document = aNode.ownerDocument;
   this.window = this.document.defaultView;
   this._parent = aNode;
-  this._showArrows = aShowArrows;
+
+  let { showArrows, showCheckboxes } = aOptions;
+  this._showArrows = showArrows || false;
+  this._showCheckboxes = showCheckboxes || false;
 
   // Create an internal scrollbox container.
   this._list = this.document.createElement("scrollbox");
   this._list.className = "side-menu-widget-container";
   this._list.setAttribute("flex", "1");
   this._list.setAttribute("orient", "vertical");
-  this._list.setAttribute("with-arrow", aShowArrows);
+  this._list.setAttribute("with-arrow", showArrows);
+  this._list.setAttribute("with-checkboxes", showCheckboxes);
   this._list.setAttribute("tabindex", "0");
   this._list.addEventListener("keypress", e => this.emit("keyPress", e), false);
   this._list.addEventListener("mousedown", e => this.emit("mousePress", e), false);
@@ -91,10 +98,12 @@ SideMenuWidget.prototype = {
    *        A tooltip attribute for the displayed item.
    * @param string aGroup [optional]
    *        The group to place the displayed item into.
+   * @param Object aAttachment [optional]
+   *        Extra data for the user.
    * @return nsIDOMNode
    *         The element associated with the displayed item.
    */
-  insertItemAt: function(aIndex, aContents, aTooltip = "", aGroup = "") {
+  insertItemAt: function(aIndex, aContents, aTooltip = "", aGroup = "", aAttachment={}) {
     aTooltip = NetworkHelper.convertToUnicode(unescape(aTooltip));
     aGroup = NetworkHelper.convertToUnicode(unescape(aGroup));
 
@@ -115,7 +124,7 @@ SideMenuWidget.prototype = {
       (this._list.scrollTop + this._list.clientHeight >= this._list.scrollHeight);
 
     let group = this._getMenuGroupForName(aGroup);
-    let item = this._getMenuItemForGroup(group, aContents, aTooltip);
+    let item = this._getMenuItemForGroup(group, aContents, aTooltip, aAttachment);
     let element = item.insertSelfAt(aIndex);
 
     if (this.maintainSelectionVisible) {
@@ -397,14 +406,17 @@ SideMenuWidget.prototype = {
    *        The string or node displayed in the container.
    * @param string aTooltip [optional]
    *        A tooltip attribute for the displayed item.
+   * @param object aAttachment [optional]
+   *        The attachement object.
    */
-  _getMenuItemForGroup: function(aGroup, aContents, aTooltip) {
-    return new SideMenuItem(aGroup, aContents, aTooltip, this._showArrows);
+  _getMenuItemForGroup: function(aGroup, aContents, aTooltip, aAttachment) {
+    return new SideMenuItem(aGroup, aContents, aTooltip, this._showArrows, this._showCheckboxes, aAttachment);
   },
 
   window: null,
   document: null,
   _showArrows: false,
+  _showCheckboxes: false,
   _parent: null,
   _list: null,
   _boxObject: null,
@@ -527,14 +539,30 @@ SideMenuGroup.prototype = {
  *        The string or node displayed in the container.
  * @param boolean aArrowFlag
  *        True if a horizontal arrow should be shown.
+ * @param boolean aCheckboxFlag
+ *        True if a checkbox should be shown.
+ * @param object aAttachment [optional]
+ *        The attachment object.
  */
-function SideMenuItem(aGroup, aContents, aTooltip, aArrowFlag) {
+function SideMenuItem(aGroup, aContents, aTooltip, aArrowFlag, aCheckboxFlag, aAttachment={}) {
   this.document = aGroup.document;
   this.window = aGroup.window;
   this.ownerView = aGroup;
 
-  // Show a horizontal arrow towards the content.
-  if (aArrowFlag) {
+  let makeCheckbox = () => {
+    let checkbox = this.document.createElement("checkbox");
+    checkbox.className = "side-menu-widget-item-checkbox";
+    checkbox.setAttribute("checked", aAttachment.checkboxState);
+    checkbox.setAttribute("tooltiptext", aAttachment.checkboxTooltip);
+    checkbox.addEventListener("command", function () {
+      ViewHelpers.dispatchEvent(checkbox, "check", {
+        checked: checkbox.checked,
+      });
+    }, false);
+    return checkbox;
+  };
+
+  if (aArrowFlag || aCheckboxFlag) {
     let container = this._container = this.document.createElement("hbox");
     container.className = "side-menu-widget-item";
     container.setAttribute("tooltiptext", aTooltip);
@@ -542,13 +570,22 @@ function SideMenuItem(aGroup, aContents, aTooltip, aArrowFlag) {
     let target = this._target = this.document.createElement("vbox");
     target.className = "side-menu-widget-item-contents";
 
-    let arrow = this._arrow = this.document.createElement("hbox");
-    arrow.className = "side-menu-widget-item-arrow";
+    // Show a checkbox before the content.
+    if (aCheckboxFlag) {
+      let checkbox = this._checkbox = makeCheckbox();
+      container.appendChild(checkbox);
+    }
 
     container.appendChild(target);
-    container.appendChild(arrow);
+
+    // Show a horizontal arrow towards the content.
+    if (aArrowFlag) {
+      let arrow = this._arrow = this.document.createElement("hbox");
+      arrow.className = "side-menu-widget-item-arrow";
+      container.appendChild(arrow);
+    }
   }
-  // Skip a few redundant nodes when no horizontal arrow is shown.
+  // Skip a few redundant nodes when no horizontal arrow or checkbox is shown.
   else {
     let target = this._target = this._container = this.document.createElement("hbox");
     target.className = "side-menu-widget-item side-menu-widget-item-contents";
diff --git a/browser/devtools/shared/widgets/ViewHelpers.jsm b/browser/devtools/shared/widgets/ViewHelpers.jsm
index b6b65d010a20..609311abd43d 100644
--- a/browser/devtools/shared/widgets/ViewHelpers.jsm
+++ b/browser/devtools/shared/widgets/ViewHelpers.jsm
@@ -11,6 +11,7 @@ const Cu = Components.utils;
 
 const PANE_APPEARANCE_DELAY = 50;
 const PAGE_SIZE_ITEM_COUNT_RATIO = 5;
+const WIDGET_FOCUSABLE_NODES = new Set(["vbox", "hbox"]);
 
 Cu.import("resource://gre/modules/Services.jsm");
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
@@ -609,7 +610,7 @@ this.WidgetMethods = {
    *          - relaxed: true if this container should allow dupes & degenerates
    *          - attachment: some attached primitive/object for the item
    *          - attributes: a batch of attributes set to the displayed element
-   *          - finalize: function invoked when the item is removed
+   *          - finalize: function invokde when the item is removed
    * @return Item
    *         The item associated with the displayed element if an unstaged push,
    *         undefined if the item was staged for a later commit.
@@ -1117,16 +1118,21 @@ this.WidgetMethods = {
   _focusChange: function(aDirection) {
     let commandDispatcher = this._commandDispatcher;
     let prevFocusedElement = commandDispatcher.focusedElement;
+    let currFocusedElement;
 
-    commandDispatcher.suppressFocusScroll = true;
-    commandDispatcher[aDirection]();
+    do {
+      commandDispatcher.suppressFocusScroll = true;
+      commandDispatcher[aDirection]();
+      currFocusedElement = commandDispatcher.focusedElement;
+
+      // Make sure the newly focused item is a part of this container. If the
+      // focus goes out of bounds, revert the previously focused item.
+      if (!this.getItemForElement(currFocusedElement)) {
+        prevFocusedElement.focus();
+        return false;
+      }
+    } while (!WIDGET_FOCUSABLE_NODES.has(currFocusedElement.tagName));
 
-    // Make sure the newly focused item is a part of this container.
-    // If the focus goes out of bounds, revert the previously focused item.
-    if (!this.getItemForElement(commandDispatcher.focusedElement)) {
-      prevFocusedElement.focus();
-      return false;
-    }
     // Focus remained within bounds.
     return true;
   },
@@ -1208,7 +1214,10 @@ this.WidgetMethods = {
    */
   getItemForElement: function(aElement) {
     while (aElement) {
-      let item = this._itemsByElement.get(aElement);
+      let item =
+        this._itemsByElement.get(aElement) ||
+        this._itemsByElement.get(aElement.nextElementSibling) ||
+        this._itemsByElement.get(aElement.previousElementSibling);
       if (item) {
         return item;
       }
diff --git a/browser/locales/en-US/chrome/browser/devtools/debugger.properties b/browser/locales/en-US/chrome/browser/devtools/debugger.properties
index f14430ed1ac8..5d6beb7caaaf 100644
--- a/browser/locales/en-US/chrome/browser/devtools/debugger.properties
+++ b/browser/locales/en-US/chrome/browser/devtools/debugger.properties
@@ -65,6 +65,11 @@ noMatchingGlobalsText=No matching globals
 # when there are no scripts.
 noSourcesText=This page has no sources.
 
+# LOCALIZATION NOTE (blackBoxCheckboxTooltip) = The tooltip text to display when
+# the user hovers over the checkbox used to toggle black boxing its associated
+# source.
+blackBoxCheckboxTooltip=Toggle black boxing
+
 # LOCALIZATION NOTE (noMatchingSourcesText): The text to display in the
 # sources menu when there are no matching scripts after filtering.
 noMatchingSourcesText=No matching sources.
diff --git a/browser/themes/linux/devtools/debugger.css b/browser/themes/linux/devtools/debugger.css
index e10bc43d727a..95c040bcf75a 100644
--- a/browser/themes/linux/devtools/debugger.css
+++ b/browser/themes/linux/devtools/debugger.css
@@ -17,6 +17,27 @@
   -moz-border-start-color: transparent;
 }
 
+.side-menu-widget-item-checkbox {
+ -moz-appearance: none;
+  padding: 0;
+  margin: 0 -4px 0 4px;
+}
+
+.side-menu-widget-item-checkbox > .checkbox-check {
+  -moz-appearance: none;
+  background: none;
+  background-image: url(itemToggle.png);
+  background-repeat: no-repeat;
+  background-clip: content-box;
+  background-position: -24px 0;
+  width: 24px;
+  height: 24px;
+}
+
+.side-menu-widget-item-checkbox[checked] > .checkbox-check {
+  background-position: 0 0;
+}
+
 /* ListWidget items */
 
 .list-widget-item {
diff --git a/browser/themes/osx/devtools/debugger.css b/browser/themes/osx/devtools/debugger.css
index 2748af514f37..90a82050c873 100644
--- a/browser/themes/osx/devtools/debugger.css
+++ b/browser/themes/osx/devtools/debugger.css
@@ -19,6 +19,27 @@
   -moz-border-start-color: transparent;
 }
 
+.side-menu-widget-item-checkbox {
+ -moz-appearance: none;
+  padding: 0;
+  margin: 0 -4px 0 4px;
+}
+
+.side-menu-widget-item-checkbox > .checkbox-check {
+  -moz-appearance: none;
+  background: none;
+  background-image: url(itemToggle.png);
+  background-repeat: no-repeat;
+  background-clip: content-box;
+  background-position: -24px 0;
+  width: 24px;
+  height: 24px;
+}
+
+.side-menu-widget-item-checkbox[checked] > .checkbox-check {
+  background-position: 0 0;
+}
+
 /* ListWidget items */
 
 .list-widget-item {
diff --git a/browser/themes/windows/devtools/debugger.css b/browser/themes/windows/devtools/debugger.css
index 2784343b433b..885aac40f6c5 100644
--- a/browser/themes/windows/devtools/debugger.css
+++ b/browser/themes/windows/devtools/debugger.css
@@ -17,6 +17,27 @@
   -moz-border-start-color: transparent;
 }
 
+.side-menu-widget-item-checkbox {
+ -moz-appearance: none;
+  padding: 0;
+  margin: 0 -4px 0 4px;
+}
+
+.side-menu-widget-item-checkbox > .checkbox-check {
+  -moz-appearance: none;
+  background: none;
+  background-image: url(itemToggle.png);
+  background-repeat: no-repeat;
+  background-clip: content-box;
+  background-position: -24px 0;
+  width: 24px;
+  height: 24px;
+}
+
+.side-menu-widget-item-checkbox[checked] > .checkbox-check {
+  background-position: 0 0;
+}
+
 /* ListWidget items */
 
 .list-widget-item {