diff --git a/browser/base/content/test/static/browser_parsable_css.js b/browser/base/content/test/static/browser_parsable_css.js
index 5ff888d8707c..cf464749cd2d 100644
--- a/browser/base/content/test/static/browser_parsable_css.js
+++ b/browser/base/content/test/static/browser_parsable_css.js
@@ -13,7 +13,7 @@ let whitelist = [
   // CodeMirror is imported as-is, see bug 1004423.
   { sourceName: /codemirror\.css$/i, isFromDevTools: true },
   {
-    sourceName: /devtools\/content\/debugger\/src\/components\/([A-z\/]+).css/i,
+    sourceName: /devtools\/client\/debugger\/src\/components\/([A-z\/]+).css/i,
     isFromDevTools: true,
   },
   // Highlighter CSS uses a UA-only pseudo-class, see bug 985597.
diff --git a/caps/nsScriptSecurityManager.cpp b/caps/nsScriptSecurityManager.cpp
index 511a2e71f59b..99742118c8ee 100644
--- a/caps/nsScriptSecurityManager.cpp
+++ b/caps/nsScriptSecurityManager.cpp
@@ -881,12 +881,24 @@ nsresult nsScriptSecurityManager::CheckLoadURIFlags(
                            &targetURIIsUIResource);
   NS_ENSURE_SUCCESS(rv, rv);
   if (targetURIIsUIResource) {
-    // ALLOW_CHROME is a flag that we pass on all loads _except_ docshell
-    // loads (since docshell loads run the loaded content with its origin
-    // principal). We are effectively allowing resource:// and chrome://
-    // URIs to load as long as they are content accessible and as long
-    // they're not loading it as a document.
     if (aFlags & nsIScriptSecurityManager::ALLOW_CHROME) {
+      // Allow a URI_IS_UI_RESOURCE source to link to a URI_IS_UI_RESOURCE
+      // target if ALLOW_CHROME is set.
+      //
+      // ALLOW_CHROME is a flag that we pass on all loads _except_ docshell
+      // loads (since docshell loads run the loaded content with its origin
+      // principal). So we're effectively allowing resource://, chrome://,
+      // and moz-icon:// source URIs to load resource://, chrome://, and
+      // moz-icon:// files, so long as they're not loading it as a document.
+      bool sourceIsUIResource;
+      rv = NS_URIChainHasFlags(aSourceBaseURI,
+                               nsIProtocolHandler::URI_IS_UI_RESOURCE,
+                               &sourceIsUIResource);
+      NS_ENSURE_SUCCESS(rv, rv);
+      if (sourceIsUIResource) {
+        return NS_OK;
+      }
+
       if (targetScheme.EqualsLiteral("resource")) {
         if (StaticPrefs::security_all_resource_uri_content_accessible()) {
           return NS_OK;
diff --git a/devtools/client/aboutdebugging/aboutdebugging.css b/devtools/client/aboutdebugging/aboutdebugging.css
index ca7d8eb3a11e..13f5cb5df9bf 100644
--- a/devtools/client/aboutdebugging/aboutdebugging.css
+++ b/devtools/client/aboutdebugging/aboutdebugging.css
@@ -5,30 +5,30 @@
 /*
 * Global styles
 */
-@import "chrome://devtools/skin/variables.css";
-@import "chrome://devtools/content/aboutdebugging/src/base.css";
+@import "resource://devtools/client/themes/variables.css";
+@import "resource://devtools/client/aboutdebugging/src/base.css";
 
 /*
 * Components
 */
-@import "chrome://devtools/content/aboutdebugging/src/components/App.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/ProfilerDialog.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/RuntimeActions.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/RuntimeInfo.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/connect/ConnectPage.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/connect/ConnectSection.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/connect/ConnectSteps.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/connect/NetworkLocationsForm.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/connect/NetworkLocationsList.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/debugtarget/DebugTargetItem.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/debugtarget/DebugTargetList.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/debugtarget/DebugTargetPane.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/debugtarget/FieldPair.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/debugtarget/ServiceWorkerAction.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/debugtarget/TemporaryExtensionInstallSection.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/shared/IconLabel.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/shared/Message.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/sidebar/Sidebar.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/sidebar/SidebarFixedItem.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/sidebar/SidebarItem.css";
-@import "chrome://devtools/content/aboutdebugging/src/components/sidebar/SidebarRuntimeItem.css";
+@import "resource://devtools/client/aboutdebugging/src/components/App.css";
+@import "resource://devtools/client/aboutdebugging/src/components/ProfilerDialog.css";
+@import "resource://devtools/client/aboutdebugging/src/components/RuntimeActions.css";
+@import "resource://devtools/client/aboutdebugging/src/components/RuntimeInfo.css";
+@import "resource://devtools/client/aboutdebugging/src/components/connect/ConnectPage.css";
+@import "resource://devtools/client/aboutdebugging/src/components/connect/ConnectSection.css";
+@import "resource://devtools/client/aboutdebugging/src/components/connect/ConnectSteps.css";
+@import "resource://devtools/client/aboutdebugging/src/components/connect/NetworkLocationsForm.css";
+@import "resource://devtools/client/aboutdebugging/src/components/connect/NetworkLocationsList.css";
+@import "resource://devtools/client/aboutdebugging/src/components/debugtarget/DebugTargetItem.css";
+@import "resource://devtools/client/aboutdebugging/src/components/debugtarget/DebugTargetList.css";
+@import "resource://devtools/client/aboutdebugging/src/components/debugtarget/DebugTargetPane.css";
+@import "resource://devtools/client/aboutdebugging/src/components/debugtarget/FieldPair.css";
+@import "resource://devtools/client/aboutdebugging/src/components/debugtarget/ServiceWorkerAction.css";
+@import "resource://devtools/client/aboutdebugging/src/components/debugtarget/TemporaryExtensionInstallSection.css";
+@import "resource://devtools/client/aboutdebugging/src/components/shared/IconLabel.css";
+@import "resource://devtools/client/aboutdebugging/src/components/shared/Message.css";
+@import "resource://devtools/client/aboutdebugging/src/components/sidebar/Sidebar.css";
+@import "resource://devtools/client/aboutdebugging/src/components/sidebar/SidebarFixedItem.css";
+@import "resource://devtools/client/aboutdebugging/src/components/sidebar/SidebarItem.css";
+@import "resource://devtools/client/aboutdebugging/src/components/sidebar/SidebarRuntimeItem.css";
diff --git a/devtools/client/aboutdebugging/src/components/connect/moz.build b/devtools/client/aboutdebugging/src/components/connect/moz.build
index b33d65ae4341..5f1e81c17908 100644
--- a/devtools/client/aboutdebugging/src/components/connect/moz.build
+++ b/devtools/client/aboutdebugging/src/components/connect/moz.build
@@ -3,9 +3,14 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 DevToolsModules(
+    'ConnectPage.css',
     'ConnectPage.js',
+    'ConnectSection.css',
     'ConnectSection.js',
+    'ConnectSteps.css',
     'ConnectSteps.js',
+    'NetworkLocationsForm.css',
     'NetworkLocationsForm.js',
+    'NetworkLocationsList.css',
     'NetworkLocationsList.js',
 )
diff --git a/devtools/client/aboutdebugging/src/components/debugtarget/moz.build b/devtools/client/aboutdebugging/src/components/debugtarget/moz.build
index 3fb310275868..eadf4fae2de3 100644
--- a/devtools/client/aboutdebugging/src/components/debugtarget/moz.build
+++ b/devtools/client/aboutdebugging/src/components/debugtarget/moz.build
@@ -3,13 +3,18 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 DevToolsModules(
+    'DebugTargetItem.css',
     'DebugTargetItem.js',
+    'DebugTargetList.css',
     'DebugTargetList.js',
+    'DebugTargetPane.css',
     'DebugTargetPane.js',
     'ExtensionDetail.js',
+    'FieldPair.css',
     'FieldPair.js',
     'InspectAction.js',
     'ProcessDetail.js',
+    'ServiceWorkerAction.css',
     'ServiceWorkerAction.js',
     'ServiceWorkerAdditionalActions.js',
     'TabAction.js',
@@ -17,6 +22,7 @@ DevToolsModules(
     'TemporaryExtensionAdditionalActions.js',
     'TemporaryExtensionDetail.js',
     'TemporaryExtensionInstaller.js',
+    'TemporaryExtensionInstallSection.css',
     'TemporaryExtensionInstallSection.js',
     'WorkerDetail.js',
 )
diff --git a/devtools/client/aboutdebugging/src/components/moz.build b/devtools/client/aboutdebugging/src/components/moz.build
index c429da00f68b..f7fd2b8f13d8 100644
--- a/devtools/client/aboutdebugging/src/components/moz.build
+++ b/devtools/client/aboutdebugging/src/components/moz.build
@@ -10,11 +10,15 @@ DIRS += [
 ]
 
 DevToolsModules(
+    'App.css',
     'App.js',
     'CompatibilityWarning.js',
     'ConnectionPromptSetting.js',
+    'ProfilerDialog.css',
     'ProfilerDialog.js',
+    'RuntimeActions.css',
     'RuntimeActions.js',
+    'RuntimeInfo.css',
     'RuntimeInfo.js',
     'RuntimePage.js',
     'ServiceWorkersWarning.js',
diff --git a/devtools/client/aboutdebugging/src/components/shared/moz.build b/devtools/client/aboutdebugging/src/components/shared/moz.build
index 22caad270f1e..beff0c33d527 100644
--- a/devtools/client/aboutdebugging/src/components/shared/moz.build
+++ b/devtools/client/aboutdebugging/src/components/shared/moz.build
@@ -4,6 +4,8 @@
 
 DevToolsModules(
     'DetailsLog.js',
+    'IconLabel.css',
     'IconLabel.js',
+    'Message.css',
     'Message.js',
 )
diff --git a/devtools/client/aboutdebugging/src/components/sidebar/moz.build b/devtools/client/aboutdebugging/src/components/sidebar/moz.build
index d308dbbb6d45..b138b2fd7f36 100644
--- a/devtools/client/aboutdebugging/src/components/sidebar/moz.build
+++ b/devtools/client/aboutdebugging/src/components/sidebar/moz.build
@@ -4,8 +4,12 @@
 
 DevToolsModules(
     'RefreshDevicesButton.js',
+    'Sidebar.css',
     'Sidebar.js',
+    'SidebarFixedItem.css',
     'SidebarFixedItem.js',
+    'SidebarItem.css',
     'SidebarItem.js',
+    'SidebarRuntimeItem.css',
     'SidebarRuntimeItem.js',
 )
diff --git a/devtools/client/aboutdebugging/src/moz.build b/devtools/client/aboutdebugging/src/moz.build
index fbb4b77a6315..e4ccec91bb07 100644
--- a/devtools/client/aboutdebugging/src/moz.build
+++ b/devtools/client/aboutdebugging/src/moz.build
@@ -12,6 +12,7 @@ DIRS += [
 ]
 
 DevToolsModules(
+    'base.css',
     'constants.js',
     'create-store.js',
 )
diff --git a/devtools/client/accessibility/index.html b/devtools/client/accessibility/index.html
index 9160ec56d57e..0eceab0443ae 100644
--- a/devtools/client/accessibility/index.html
+++ b/devtools/client/accessibility/index.html
@@ -9,11 +9,11 @@
 
   <link href="chrome://devtools/skin/badge.css" rel="stylesheet" />
   <link href="chrome://devtools/skin/accessibility-color-contrast.css" rel="stylesheet" />
-  <link href="chrome://devtools/content/accessibility/accessibility.css" rel="stylesheet"/>
-  <link href="chrome://devtools/content/shared/components/splitter/SplitBox.css" rel="stylesheet" />
-  <link href="chrome://devtools/content/shared/components/Accordion.css" rel="stylesheet" />
-  <link href="chrome://devtools/content/shared/components/List.css" rel="stylesheet" />
-  <link href="chrome://devtools/content/shared/components/tree/TreeView.css" rel="stylesheet" />
+  <link href="resource://devtools/client/accessibility/accessibility.css" rel="stylesheet"/>
+  <link href="resource://devtools/client/shared/components/splitter/SplitBox.css" rel="stylesheet" />
+  <link href="resource://devtools/client/shared/components/Accordion.css" rel="stylesheet" />
+  <link href="resource://devtools/client/shared/components/List.css" rel="stylesheet" />
+  <link href="resource://devtools/client/shared/components/tree/TreeView.css" rel="stylesheet" />
 
   <script src="chrome://devtools/content/shared/theme-switching.js"></script>
 </head>
diff --git a/devtools/client/accessibility/moz.build b/devtools/client/accessibility/moz.build
index aacfbe463868..b39e216942e2 100644
--- a/devtools/client/accessibility/moz.build
+++ b/devtools/client/accessibility/moz.build
@@ -16,6 +16,7 @@ DevToolsModules(
     'accessibility-proxy.js',
     'accessibility-startup.js',
     'accessibility-view.js',
+    'accessibility.css',
     'constants.js',
     'panel.js',
     'picker.js',
diff --git a/devtools/client/application/application.css b/devtools/client/application/application.css
index 3001ec22b867..2526886d8717 100644
--- a/devtools/client/application/application.css
+++ b/devtools/client/application/application.css
@@ -5,28 +5,28 @@
  /*
 * Global styles
 */
-@import "chrome://devtools/content/application/src/base.css";
+@import "resource://devtools/client/application/src/base.css";
 
 /*
 * Components
 */
-@import "chrome://devtools/content/application/src/components/App.css";
-@import "chrome://devtools/content/application/src/components/manifest/ManifestColorItem.css";
-@import "chrome://devtools/content/application/src/components/manifest/ManifestIconItem.css";
-@import "chrome://devtools/content/application/src/components/manifest/ManifestIssue.css";
-@import "chrome://devtools/content/application/src/components/manifest/ManifestIssueList.css";
-@import "chrome://devtools/content/application/src/components/manifest/ManifestItem.css";
-@import "chrome://devtools/content/application/src/components/manifest/ManifestJsonLink.css";
-@import "chrome://devtools/content/application/src/components/manifest/ManifestLoader.css";
-@import "chrome://devtools/content/application/src/components/manifest/ManifestSection.css";
-@import "chrome://devtools/content/application/src/components/routing/PageSwitcher.css";
-@import "chrome://devtools/content/application/src/components/routing/Sidebar.css";
-@import "chrome://devtools/content/application/src/components/routing/SidebarItem.css";
-@import "chrome://devtools/content/application/src/components/service-workers/Registration.css";
-@import "chrome://devtools/content/application/src/components/service-workers/RegistrationList.css";
-@import "chrome://devtools/content/application/src/components/service-workers/RegistrationListEmpty.css";
-@import "chrome://devtools/content/application/src/components/service-workers/Worker.css";
-@import "chrome://devtools/content/application/src/components/ui/UIButton.css";
+@import "resource://devtools/client/application/src/components/App.css";
+@import "resource://devtools/client/application/src/components/manifest/ManifestColorItem.css";
+@import "resource://devtools/client/application/src/components/manifest/ManifestIconItem.css";
+@import "resource://devtools/client/application/src/components/manifest/ManifestIssue.css";
+@import "resource://devtools/client/application/src/components/manifest/ManifestIssueList.css";
+@import "resource://devtools/client/application/src/components/manifest/ManifestItem.css";
+@import "resource://devtools/client/application/src/components/manifest/ManifestJsonLink.css";
+@import "resource://devtools/client/application/src/components/manifest/ManifestLoader.css";
+@import "resource://devtools/client/application/src/components/manifest/ManifestSection.css";
+@import "resource://devtools/client/application/src/components/routing/PageSwitcher.css";
+@import "resource://devtools/client/application/src/components/routing/Sidebar.css";
+@import "resource://devtools/client/application/src/components/routing/SidebarItem.css";
+@import "resource://devtools/client/application/src/components/service-workers/Registration.css";
+@import "resource://devtools/client/application/src/components/service-workers/RegistrationList.css";
+@import "resource://devtools/client/application/src/components/service-workers/RegistrationListEmpty.css";
+@import "resource://devtools/client/application/src/components/service-workers/Worker.css";
+@import "resource://devtools/client/application/src/components/ui/UIButton.css";
 
 html,
 body,
diff --git a/devtools/client/application/index.html b/devtools/client/application/index.html
index b886735ca552..727af8658199 100644
--- a/devtools/client/application/index.html
+++ b/devtools/client/application/index.html
@@ -5,7 +5,7 @@
 <html dir="">
   <head>
     <meta http-equiv="Content-Security-Policy" content="default-src chrome: resource:; img-src http: https: data: chrome:;">
-    <link rel="stylesheet" type="text/css" href="chrome://devtools/content/application/application.css" />
+    <link rel="stylesheet" type="text/css" href="resource://devtools/client/application/application.css" />
   </head>
   <body class="theme-body" role="application">
     <div id="mount"></div>
diff --git a/devtools/client/application/moz.build b/devtools/client/application/moz.build
index 1d3565991ec8..1cb34dc02d8d 100644
--- a/devtools/client/application/moz.build
+++ b/devtools/client/application/moz.build
@@ -7,6 +7,7 @@ DIRS += [
 ]
 
 DevToolsModules(
+    'application.css',
     'initializer.js',
     'panel.js'
 )
diff --git a/devtools/client/application/src/components/manifest/moz.build b/devtools/client/application/src/components/manifest/moz.build
index 217319ab9a61..33d6da3f849a 100644
--- a/devtools/client/application/src/components/manifest/moz.build
+++ b/devtools/client/application/src/components/manifest/moz.build
@@ -4,14 +4,22 @@
 
 DevToolsModules(
     'Manifest.js',
+	'ManifestColorItem.css',
     'ManifestColorItem.js',
     'ManifestEmpty.js',
+    'ManifestIconItem.css',
     'ManifestIconItem.js',
+	'ManifestIssue.css',
 	'ManifestIssue.js',
+	'ManifestIssueList.css',
 	'ManifestIssueList.js',
+    'ManifestItem.css',
     'ManifestItem.js',
+    'ManifestJsonLink.css',
     'ManifestJsonLink.js',
+    'ManifestLoader.css',
     'ManifestLoader.js',
     'ManifestPage.js',
+    'ManifestSection.css',
     'ManifestSection.js',
 )
diff --git a/devtools/client/application/src/components/moz.build b/devtools/client/application/src/components/moz.build
index eaedf97ac789..06e5987d81d7 100644
--- a/devtools/client/application/src/components/moz.build
+++ b/devtools/client/application/src/components/moz.build
@@ -10,5 +10,6 @@ DIRS += [
 ]
 
 DevToolsModules(
+    'App.css',
     'App.js',
 )
diff --git a/devtools/client/application/src/components/routing/moz.build b/devtools/client/application/src/components/routing/moz.build
index 4fa4f49057c8..bc7efb930632 100644
--- a/devtools/client/application/src/components/routing/moz.build
+++ b/devtools/client/application/src/components/routing/moz.build
@@ -3,7 +3,10 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 DevToolsModules(
+    'PageSwitcher.css',
     'PageSwitcher.js',
+    'Sidebar.css',
     'Sidebar.js',
+    'SidebarItem.css',
     'SidebarItem.js'
 )
diff --git a/devtools/client/application/src/components/service-workers/moz.build b/devtools/client/application/src/components/service-workers/moz.build
index 187758a5920c..ea2d5e26eef3 100644
--- a/devtools/client/application/src/components/service-workers/moz.build
+++ b/devtools/client/application/src/components/service-workers/moz.build
@@ -3,9 +3,13 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 DevToolsModules(
+    'Registration.css',
     'Registration.js',
+    'RegistrationList.css',
     'RegistrationList.js',
+    'RegistrationListEmpty.css',
     'RegistrationListEmpty.js',
+    'Worker.css',
     'Worker.js',
     'WorkersPage.js',
 )
diff --git a/devtools/client/application/src/components/ui/moz.build b/devtools/client/application/src/components/ui/moz.build
index d1e10ee710a5..102f43a2012d 100644
--- a/devtools/client/application/src/components/ui/moz.build
+++ b/devtools/client/application/src/components/ui/moz.build
@@ -3,5 +3,6 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 DevToolsModules(
+    'UIButton.css',
     'UIButton.js',
 )
diff --git a/devtools/client/application/src/moz.build b/devtools/client/application/src/moz.build
index 45aac5855bda..3af6532b0d1f 100644
--- a/devtools/client/application/src/moz.build
+++ b/devtools/client/application/src/moz.build
@@ -11,6 +11,7 @@ DIRS += [
 ]
 
 DevToolsModules(
+	'base.css',
     'constants.js',
     'create-store.js',
 )
diff --git a/devtools/client/debugger/dist/moz.build b/devtools/client/debugger/dist/moz.build
index 471f1445f007..ac5553ca49ec 100644
--- a/devtools/client/debugger/dist/moz.build
+++ b/devtools/client/debugger/dist/moz.build
@@ -7,5 +7,6 @@ DevToolsModules(
     'parser-worker.js',
     'pretty-print-worker.js',
     'search-worker.js',
+    'vendors.css',
     'vendors.js',
 )
diff --git a/devtools/client/debugger/index.html b/devtools/client/debugger/index.html
index ec934d925dda..84d33e97efb2 100644
--- a/devtools/client/debugger/index.html
+++ b/devtools/client/debugger/index.html
@@ -22,17 +22,17 @@
     <link
       rel="stylesheet"
       type="text/css"
-      href="chrome://devtools/content/shared/components/reps/reps.css"
+      href="resource://devtools/client/shared/components/reps/reps.css"
     />
     <link
       rel="stylesheet"
       type="text/css"
-      href="chrome://devtools/content/debugger/dist/vendors.css"
+      href="resource://devtools/client/debugger/dist/vendors.css"
     />
     <link
       rel="stylesheet"
       type="text/css"
-      href="chrome://devtools/content/debugger/src/debugger.css"
+      href="resource://devtools/client/debugger/src/debugger.css"
     />
   </head>
 
diff --git a/devtools/client/debugger/src/components/Editor/Preview/moz.build b/devtools/client/debugger/src/components/Editor/Preview/moz.build
index ffdad73a01d7..cf2838087223 100644
--- a/devtools/client/debugger/src/components/Editor/Preview/moz.build
+++ b/devtools/client/debugger/src/components/Editor/Preview/moz.build
@@ -11,3 +11,7 @@ CompiledModules(
     'index.js',
     'Popup.js',
 )
+
+DevToolsModules(
+    'Popup.css',
+)
diff --git a/devtools/client/debugger/src/components/Editor/moz.build b/devtools/client/debugger/src/components/Editor/moz.build
index 4797ea870187..3910152df465 100644
--- a/devtools/client/debugger/src/components/Editor/moz.build
+++ b/devtools/client/debugger/src/components/Editor/moz.build
@@ -31,3 +31,15 @@ CompiledModules(
     'Tab.js',
     'Tabs.js',
 )
+
+DevToolsModules(
+    'Breakpoints.css',
+    'ConditionalPanel.css',
+    'Editor.css',
+    'Footer.css',
+    'HighlightCalls.css',
+    'InlinePreview.css',
+    'Preview.css',
+    'SearchBar.css',
+    'Tabs.css',
+)
diff --git a/devtools/client/debugger/src/components/PrimaryPanes/moz.build b/devtools/client/debugger/src/components/PrimaryPanes/moz.build
index 74109f29921c..50767a414ce4 100644
--- a/devtools/client/debugger/src/components/PrimaryPanes/moz.build
+++ b/devtools/client/debugger/src/components/PrimaryPanes/moz.build
@@ -14,3 +14,9 @@ CompiledModules(
     'SourcesTree.js',
     'SourcesTreeItem.js',
 )
+
+DevToolsModules(
+    'Outline.css',
+    'OutlineFilter.css',
+    'Sources.css',
+)
diff --git a/devtools/client/debugger/src/components/SecondaryPanes/Breakpoints/moz.build b/devtools/client/debugger/src/components/SecondaryPanes/Breakpoints/moz.build
index 41c50f67965d..2bc6d610adda 100644
--- a/devtools/client/debugger/src/components/SecondaryPanes/Breakpoints/moz.build
+++ b/devtools/client/debugger/src/components/SecondaryPanes/Breakpoints/moz.build
@@ -15,3 +15,7 @@ CompiledModules(
     'ExceptionOption.js',
     'index.js',
 )
+
+DevToolsModules(
+    'Breakpoints.css',
+)
diff --git a/devtools/client/debugger/src/components/SecondaryPanes/Frames/moz.build b/devtools/client/debugger/src/components/SecondaryPanes/Frames/moz.build
index 7855fc896ba6..89856f34bac8 100644
--- a/devtools/client/debugger/src/components/SecondaryPanes/Frames/moz.build
+++ b/devtools/client/debugger/src/components/SecondaryPanes/Frames/moz.build
@@ -14,3 +14,8 @@ CompiledModules(
     'Group.js',
     'index.js',
 )
+
+DevToolsModules(
+    'Frames.css',
+    'Group.css',
+)
diff --git a/devtools/client/debugger/src/components/SecondaryPanes/moz.build b/devtools/client/debugger/src/components/SecondaryPanes/moz.build
index 664d2b80d84b..9723cba969a0 100644
--- a/devtools/client/debugger/src/components/SecondaryPanes/moz.build
+++ b/devtools/client/debugger/src/components/SecondaryPanes/moz.build
@@ -20,3 +20,15 @@ CompiledModules(
     'WhyPaused.js',
     'XHRBreakpoints.js',
 )
+
+DevToolsModules(
+    'CommandBar.css',
+    'DOMMutationBreakpoints.css',
+    'EventListeners.css',
+    'Expressions.css',
+    'Scopes.css',
+    'SecondaryPanes.css',
+    'Threads.css',
+    'WhyPaused.css',
+    'XHRBreakpoints.css',
+)
diff --git a/devtools/client/debugger/src/components/moz.build b/devtools/client/debugger/src/components/moz.build
index 8630b23e7841..c2f414e31caa 100644
--- a/devtools/client/debugger/src/components/moz.build
+++ b/devtools/client/debugger/src/components/moz.build
@@ -18,3 +18,13 @@ CompiledModules(
     'ShortcutsModal.js',
     'WelcomeBox.js',
 )
+
+DevToolsModules(
+    'A11yIntention.css',
+    'App.css',
+    'ProjectSearch.css',
+    'QuickOpenModal.css',
+    'ShortcutsModal.css',
+    'variables.css',
+    'WelcomeBox.css',
+)
diff --git a/devtools/client/debugger/src/components/shared/Button/styles/moz.build b/devtools/client/debugger/src/components/shared/Button/styles/moz.build
index 3ebd4a0c9b4e..98cc709c58b2 100644
--- a/devtools/client/debugger/src/components/shared/Button/styles/moz.build
+++ b/devtools/client/debugger/src/components/shared/Button/styles/moz.build
@@ -10,3 +10,9 @@ DIRS += [
 CompiledModules(
 
 )
+
+DevToolsModules(
+    'CloseButton.css',
+    'CommandBarButton.css',
+    'PaneToggleButton.css',
+)
diff --git a/devtools/client/debugger/src/components/shared/moz.build b/devtools/client/debugger/src/components/shared/moz.build
index 104fb3f7c322..13eeb9c2f32f 100644
--- a/devtools/client/debugger/src/components/shared/moz.build
+++ b/devtools/client/debugger/src/components/shared/moz.build
@@ -22,3 +22,19 @@ CompiledModules(
     'SourceIcon.js',
     'SmartGap.js',
 )
+
+DevToolsModules(
+    'AccessibleImage.css',
+    'Accordion.css',
+    'Badge.css',
+    'BracketArrow.css',
+    'Dropdown.css',
+    'ManagedTree.css',
+    'menu.css',
+    'Modal.css',
+    'Popover.css',
+    'PreviewFunction.css',
+    'ResultList.css',
+    'SearchInput.css',
+    'SourceIcon.css',
+)
diff --git a/devtools/client/debugger/src/debugger.css b/devtools/client/debugger/src/debugger.css
index 46fe7260af26..51418bc57c24 100644
--- a/devtools/client/debugger/src/debugger.css
+++ b/devtools/client/debugger/src/debugger.css
@@ -2,56 +2,56 @@
  * 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/. */
 
-@import url("chrome://devtools/content/debugger/src/components/variables.css");
-@import url("chrome://devtools/content/shared/components/reps/reps.css");
+@import url("./components/variables.css");
+@import url("resource://devtools/client/shared/components/reps/reps.css");
 
-@import url("chrome://devtools/content/debugger/src/components/A11yIntention.css");
-@import url("chrome://devtools/content/debugger/src/components/App.css");
+@import url("./components/A11yIntention.css");
+@import url("./components/App.css");
 
-@import url("chrome://devtools/content/debugger/src/components/shared/AccessibleImage.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/Accordion.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/Badge.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/BracketArrow.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/Button/styles/CloseButton.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/Button/styles/CommandBarButton.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/Button/styles/PaneToggleButton.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/Dropdown.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/ManagedTree.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/menu.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/Modal.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/Popover.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/PreviewFunction.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/ResultList.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/SearchInput.css");
-@import url("chrome://devtools/content/debugger/src/components/shared/SourceIcon.css");
+@import url("./components/shared/AccessibleImage.css");
+@import url("./components/shared/Accordion.css");
+@import url("./components/shared/Badge.css");
+@import url("./components/shared/BracketArrow.css");
+@import url("./components/shared/Button/styles/CloseButton.css");
+@import url("./components/shared/Button/styles/CommandBarButton.css");
+@import url("./components/shared/Button/styles/PaneToggleButton.css");
+@import url("./components/shared/Dropdown.css");
+@import url("./components/shared/ManagedTree.css");
+@import url("./components/shared/menu.css");
+@import url("./components/shared/Modal.css");
+@import url("./components/shared/Popover.css");
+@import url("./components/shared/PreviewFunction.css");
+@import url("./components/shared/ResultList.css");
+@import url("./components/shared/SearchInput.css");
+@import url("./components/shared/SourceIcon.css");
 
-@import url("chrome://devtools/content/debugger/src/components/Editor/Breakpoints.css");
-@import url("chrome://devtools/content/debugger/src/components/Editor/ConditionalPanel.css");
-@import url("chrome://devtools/content/debugger/src/components/Editor/Editor.css");
-@import url("chrome://devtools/content/debugger/src/components/Editor/Footer.css");
-@import url("chrome://devtools/content/debugger/src/components/Editor/InlinePreview.css");
-@import url("chrome://devtools/content/debugger/src/components/Editor/Preview.css");
-@import url("chrome://devtools/content/debugger/src/components/Editor/Preview/Popup.css");
-@import url("chrome://devtools/content/debugger/src/components/Editor/HighlightCalls.css");
-@import url("chrome://devtools/content/debugger/src/components/Editor/SearchBar.css");
-@import url("chrome://devtools/content/debugger/src/components/Editor/Tabs.css");
-@import url("chrome://devtools/content/debugger/src/components/PrimaryPanes/Outline.css");
-@import url("chrome://devtools/content/debugger/src/components/PrimaryPanes/OutlineFilter.css");
-@import url("chrome://devtools/content/debugger/src/components/PrimaryPanes/Sources.css");
-@import url("chrome://devtools/content/debugger/src/components/ProjectSearch.css");
-@import url("chrome://devtools/content/debugger/src/components/QuickOpenModal.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/Breakpoints/Breakpoints.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/CommandBar.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/EventListeners.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/DOMMutationBreakpoints.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/Expressions.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/Frames/Frames.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/Frames/Group.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/Scopes.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/SecondaryPanes.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/WhyPaused.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/Threads.css");
-@import url("chrome://devtools/content/debugger/src/components/SecondaryPanes/XHRBreakpoints.css");
-@import url("chrome://devtools/content/debugger/src/components/ShortcutsModal.css");
-@import url("chrome://devtools/content/debugger/src/components/WelcomeBox.css");
-@import url("chrome://devtools/content/debugger/src/utils/editor/source-editor.css");
+@import url("./components/Editor/Breakpoints.css");
+@import url("./components/Editor/ConditionalPanel.css");
+@import url("./components/Editor/Editor.css");
+@import url("./components/Editor/Footer.css");
+@import url("./components/Editor/InlinePreview.css");
+@import url("./components/Editor/Preview.css");
+@import url("./components/Editor/Preview/Popup.css");
+@import url("./components/Editor/HighlightCalls.css");
+@import url("./components/Editor/SearchBar.css");
+@import url("./components/Editor/Tabs.css");
+@import url("./components/PrimaryPanes/Outline.css");
+@import url("./components/PrimaryPanes/OutlineFilter.css");
+@import url("./components/PrimaryPanes/Sources.css");
+@import url("./components/ProjectSearch.css");
+@import url("./components/QuickOpenModal.css");
+@import url("./components/SecondaryPanes/Breakpoints/Breakpoints.css");
+@import url("./components/SecondaryPanes/CommandBar.css");
+@import url("./components/SecondaryPanes/EventListeners.css");
+@import url("./components/SecondaryPanes/DOMMutationBreakpoints.css");
+@import url("./components/SecondaryPanes/Expressions.css");
+@import url("./components/SecondaryPanes/Frames/Frames.css");
+@import url("./components/SecondaryPanes/Frames/Group.css");
+@import url("./components/SecondaryPanes/Scopes.css");
+@import url("./components/SecondaryPanes/SecondaryPanes.css");
+@import url("./components/SecondaryPanes/WhyPaused.css");
+@import url("./components/SecondaryPanes/Threads.css");
+@import url("./components/SecondaryPanes/XHRBreakpoints.css");
+@import url("./components/ShortcutsModal.css");
+@import url("./components/WelcomeBox.css");
+@import url("./utils/editor/source-editor.css");
diff --git a/devtools/client/debugger/src/moz.build b/devtools/client/debugger/src/moz.build
index 92737286e344..801fefc5b241 100644
--- a/devtools/client/debugger/src/moz.build
+++ b/devtools/client/debugger/src/moz.build
@@ -18,3 +18,7 @@ CompiledModules(
     'main.js',
     'vendors.js',
 )
+
+DevToolsModules(
+    'debugger.css',
+)
diff --git a/devtools/client/debugger/src/utils/editor/moz.build b/devtools/client/debugger/src/utils/editor/moz.build
index 2727b06ffc46..70de08ca31a0 100644
--- a/devtools/client/debugger/src/utils/editor/moz.build
+++ b/devtools/client/debugger/src/utils/editor/moz.build
@@ -17,3 +17,7 @@ CompiledModules(
     'source-search.js',
     'token-events.js',
 )
+
+DevToolsModules(
+    'source-editor.css',
+)
diff --git a/devtools/client/debugger/src/utils/editor/source-editor.js b/devtools/client/debugger/src/utils/editor/source-editor.js
index 5b3a46907a08..78658a3a3b3e 100644
--- a/devtools/client/debugger/src/utils/editor/source-editor.js
+++ b/devtools/client/debugger/src/utils/editor/source-editor.js
@@ -12,7 +12,7 @@
 const CodeMirror = require("codemirror");
 
 // $FlowIgnore
-require("raw!chrome://devtools/content/shared/sourceeditor/codemirror/lib/codemirror.css");
+require("codemirror/lib/codemirror.css");
 require("codemirror/mode/javascript/javascript");
 require("codemirror/mode/htmlmixed/htmlmixed");
 require("codemirror/mode/coffeescript/coffeescript");
@@ -32,7 +32,7 @@ require("codemirror/addon/display/placeholder");
 require("codemirror/mode/clike/clike");
 require("codemirror/mode/rust/rust");
 
-require("raw!chrome://devtools/content/debugger/src/utils/editor/source-editor.css");
+require("./source-editor.css");
 
 // NOTE: we should eventually use debugger-html context type mode
 type Mode = string | Object;
diff --git a/devtools/client/dom/content/moz.build b/devtools/client/dom/content/moz.build
index ddf6dbca32a7..b4a9c76bfbd0 100644
--- a/devtools/client/dom/content/moz.build
+++ b/devtools/client/dom/content/moz.build
@@ -12,6 +12,7 @@ DIRS += [
 DevToolsModules(
     'constants.js',
     'dom-decorator.js',
+    'dom-view.css',
     'dom-view.js',
     'grip-provider.js',
     'utils.js',
diff --git a/devtools/client/dom/index.html b/devtools/client/dom/index.html
index 0e4fd84b769f..1cefa3b99375 100644
--- a/devtools/client/dom/index.html
+++ b/devtools/client/dom/index.html
@@ -7,9 +7,9 @@
 <head>
   <meta charset="utf-8"/>
 
-  <link href="chrome://devtools/content/dom/content/dom-view.css" rel="stylesheet" />
-  <link href="chrome://devtools-jsonview-styles/content/toolbar.css" rel="stylesheet" />
-  <link href="chrome://devtools/content/shared/components/tree/TreeView.css" rel="stylesheet" />
+  <link href="resource://devtools/client/dom/content/dom-view.css" rel="stylesheet" />
+  <link href="resource://devtools/client/jsonview/css/toolbar.css" rel="stylesheet" />
+  <link href="resource://devtools/client/shared/components/tree/TreeView.css" rel="stylesheet" />
 
   <script src="chrome://devtools/content/shared/theme-switching.js"></script>
 </head>
diff --git a/devtools/client/framework/browser-toolbox/window.html b/devtools/client/framework/browser-toolbox/window.html
index 6043a9e5bcab..ae89030ca69f 100644
--- a/devtools/client/framework/browser-toolbox/window.html
+++ b/devtools/client/framework/browser-toolbox/window.html
@@ -8,7 +8,7 @@
       persist="screenX screenY width height sizemode">
   <head>
     <link rel="stylesheet" href="chrome://global/skin/global.css"/>
-    <link rel="stylesheet" href="chrome://devtools/skin/common.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/themes/common.css"/>
     <link rel="stylesheet" href="chrome://devtools/content/framework/browser-toolbox/window.css"/>
     <script src="chrome://global/content/globalOverlay.js"></script>
     <script src="chrome://devtools/content/framework/browser-toolbox/window.js"></script>
diff --git a/devtools/client/framework/components/moz.build b/devtools/client/framework/components/moz.build
index 3cde71701ea8..384b2201089b 100644
--- a/devtools/client/framework/components/moz.build
+++ b/devtools/client/framework/components/moz.build
@@ -6,6 +6,7 @@
 
 
 DevToolsModules(
+  'DebugTargetErrorPage.css',
   'DebugTargetErrorPage.js',
   'DebugTargetInfo.js',
   'MeatballMenu.js',
diff --git a/devtools/client/framework/toolbox.xhtml b/devtools/client/framework/toolbox.xhtml
index 91ba0826c0e7..4e97c55db908 100644
--- a/devtools/client/framework/toolbox.xhtml
+++ b/devtools/client/framework/toolbox.xhtml
@@ -4,8 +4,8 @@
    - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
 <?xml-stylesheet href="chrome://global/skin/global.css" type="text/css"?>
 <?xml-stylesheet href="chrome://devtools/skin/toolbox.css" type="text/css"?>
-<?xml-stylesheet href="chrome://devtools/content/shared/components/NotificationBox.css" type="text/css"?>
-<?xml-stylesheet href="chrome://devtools/content/framework/components/DebugTargetErrorPage.css" type="text/css"?>
+<?xml-stylesheet href="resource://devtools/client/shared/components/NotificationBox.css" type="text/css"?>
+<?xml-stylesheet href="resource://devtools/client/framework/components/DebugTargetErrorPage.css" type="text/css"?>
 
 
 <!DOCTYPE window>
diff --git a/devtools/client/inspector/components/moz.build b/devtools/client/inspector/components/moz.build
index 0bb0fd189847..eb97966c12b2 100644
--- a/devtools/client/inspector/components/moz.build
+++ b/devtools/client/inspector/components/moz.build
@@ -5,5 +5,6 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 DevToolsModules(
+    'InspectorTabPanel.css',
     'InspectorTabPanel.js',
 )
diff --git a/devtools/client/inspector/index.xhtml b/devtools/client/inspector/index.xhtml
index 118e1f0b8be3..1f77bfcee58d 100644
--- a/devtools/client/inspector/index.xhtml
+++ b/devtools/client/inspector/index.xhtml
@@ -19,13 +19,13 @@
   <link rel="stylesheet" href="chrome://devtools/skin/boxmodel.css"/>
   <link rel="stylesheet" href="chrome://devtools/skin/layout.css"/>
   <link rel="stylesheet" href="chrome://devtools/skin/animation.css"/>
-  <link rel="stylesheet" href="chrome://devtools/content/shared/components/tabs/Tabs.css"/>
-  <link rel="stylesheet" href="chrome://devtools/content/shared/components/SidebarToggle.css"/>
-  <link rel="stylesheet" href="chrome://devtools/content/inspector/components/InspectorTabPanel.css"/>
-  <link rel="stylesheet" href="chrome://devtools/content/shared/components/splitter/SplitBox.css"/>
-  <link rel="stylesheet" href="chrome://devtools/content/shared/components/Accordion.css"/>
-  <link rel="stylesheet" href="chrome://devtools/content/shared/components/reps/reps.css"/>
-  <link rel="stylesheet" href="chrome://devtools/content/shared/components/tree/TreeView.css"/>
+  <link rel="stylesheet" href="resource://devtools/client/shared/components/tabs/Tabs.css"/>
+  <link rel="stylesheet" href="resource://devtools/client/shared/components/SidebarToggle.css"/>
+  <link rel="stylesheet" href="resource://devtools/client/inspector/components/InspectorTabPanel.css"/>
+  <link rel="stylesheet" href="resource://devtools/client/shared/components/splitter/SplitBox.css"/>
+  <link rel="stylesheet" href="resource://devtools/client/shared/components/Accordion.css"/>
+  <link rel="stylesheet" href="resource://devtools/client/shared/components/reps/reps.css"/>
+  <link rel="stylesheet" href="resource://devtools/client/shared/components/tree/TreeView.css"/>
 
   <script src="chrome://devtools/content/shared/theme-switching.js"></script>
   <script>
diff --git a/devtools/client/jar.mn b/devtools/client/jar.mn
index afa34e6734e4..e539c541a210 100644
--- a/devtools/client/jar.mn
+++ b/devtools/client/jar.mn
@@ -8,17 +8,12 @@ devtools.jar:
     content/shared/vendor/dagre-d3.js (shared/vendor/dagre-d3.js)
     content/shared/widgets/widgets.css (shared/widgets/widgets.css)
     content/webconsole/index.html (webconsole/index.html)
-    content/webconsole/components/Input/EagerEvaluation.css (webconsole/components/Input/EagerEvaluation.css)
-    content/webconsole/components/Input/EvaluationContextSelector.css (webconsole/components/Input/EvaluationContextSelector.css)
-    content/webconsole/components/Input/ReverseSearchInput.css (webconsole/components/Input/ReverseSearchInput.css)
-    content/webconsole/components/App.css (webconsole/components/App.css)
     content/shared/splitview.css (shared/splitview.css)
     content/shared/toolbarbutton.css (shared/toolbarbutton.css)
     content/shared/theme-switching.js (shared/theme-switching.js)
     content/styleeditor/index.xhtml (styleeditor/index.xhtml)
     content/storage/index.xhtml (storage/index.xhtml)
     content/inspector/markup/markup.xhtml (inspector/markup/markup.xhtml)
-    content/inspector/components/InspectorTabPanel.css (inspector/components/InspectorTabPanel.css)
     content/shared/sourceeditor/codemirror/addon/dialog/dialog.css (shared/sourceeditor/codemirror/addon/dialog/dialog.css)
     content/shared/sourceeditor/codemirror/keymap/emacs.js (shared/sourceeditor/codemirror/keymap/emacs.js)
     content/shared/sourceeditor/codemirror/keymap/vim.js (shared/sourceeditor/codemirror/keymap/vim.js)
@@ -28,57 +23,6 @@ devtools.jar:
     content/shared/sourceeditor/codemirror/mozilla.css (shared/sourceeditor/codemirror/mozilla.css)
     content/shared/sourceeditor/codemirror/cmiframe.html (shared/sourceeditor/codemirror/cmiframe.html)
     content/debugger/index.html (debugger/index.html)
-    content/debugger/dist/vendors.css (debugger/dist/vendors.css)
-    content/debugger/src/debugger.css (debugger/src/debugger.css)
-    content/debugger/src/components/variables.css (debugger/src/components/variables.css)
-    content/debugger/src/components/A11yIntention.css (debugger/src/components/A11yIntention.css)
-    content/debugger/src/components/App.css (debugger/src/components/App.css)
-    content/debugger/src/components/ProjectSearch.css (debugger/src/components/ProjectSearch.css)
-    content/debugger/src/components/QuickOpenModal.css (debugger/src/components/QuickOpenModal.css)
-    content/debugger/src/components/ShortcutsModal.css (debugger/src/components/ShortcutsModal.css)
-    content/debugger/src/components/WelcomeBox.css (debugger/src/components/WelcomeBox.css)
-    content/debugger/src/components/shared/AccessibleImage.css (debugger/src/components/shared/AccessibleImage.css)
-    content/debugger/src/components/shared/Accordion.css (debugger/src/components/shared/Accordion.css)
-    content/debugger/src/components/shared/Badge.css (debugger/src/components/shared/Badge.css)
-    content/debugger/src/components/shared/BracketArrow.css (debugger/src/components/shared/BracketArrow.css)
-    content/debugger/src/components/shared/Button/styles/CloseButton.css (debugger/src/components/shared/Button/styles/CloseButton.css)
-    content/debugger/src/components/shared/Button/styles/CommandBarButton.css (debugger/src/components/shared/Button/styles/CommandBarButton.css)
-    content/debugger/src/components/shared/Button/styles/PaneToggleButton.css (debugger/src/components/shared/Button/styles/PaneToggleButton.css)
-    content/debugger/src/components/shared/Dropdown.css (debugger/src/components/shared/Dropdown.css)
-    content/debugger/src/components/shared/ManagedTree.css (debugger/src/components/shared/ManagedTree.css)
-    content/debugger/src/components/shared/menu.css (debugger/src/components/shared/menu.css)
-    content/debugger/src/components/shared/Modal.css (debugger/src/components/shared/Modal.css)
-    content/debugger/src/components/shared/Popover.css (debugger/src/components/shared/Popover.css)
-    content/debugger/src/components/shared/PreviewFunction.css (debugger/src/components/shared/PreviewFunction.css)
-    content/debugger/src/components/shared/ResultList.css (debugger/src/components/shared/ResultList.css)
-    content/debugger/src/components/shared/SearchInput.css (debugger/src/components/shared/SearchInput.css)
-    content/debugger/src/components/shared/SourceIcon.css (debugger/src/components/shared/SourceIcon.css)
-    content/debugger/src/components/Editor/Breakpoints.css (debugger/src/components/Editor/Breakpoints.css)
-    content/debugger/src/components/Editor/ConditionalPanel.css (debugger/src/components/Editor/ConditionalPanel.css)
-    content/debugger/src/components/Editor/Editor.css (debugger/src/components/Editor/Editor.css)
-    content/debugger/src/components/Editor/Footer.css (debugger/src/components/Editor/Footer.css)
-    content/debugger/src/components/Editor/InlinePreview.css (debugger/src/components/Editor/InlinePreview.css)
-    content/debugger/src/components/Editor/Preview.css (debugger/src/components/Editor/Preview.css)
-    content/debugger/src/components/Editor/Preview/Popup.css (debugger/src/components/Editor/Preview/Popup.css)
-    content/debugger/src/components/Editor/HighlightCalls.css (debugger/src/components/Editor/HighlightCalls.css)
-    content/debugger/src/components/Editor/SearchBar.css (debugger/src/components/Editor/SearchBar.css)
-    content/debugger/src/components/Editor/Tabs.css (debugger/src/components/Editor/Tabs.css)
-    content/debugger/src/components/PrimaryPanes/Outline.css (debugger/src/components/PrimaryPanes/Outline.css)
-    content/debugger/src/components/PrimaryPanes/OutlineFilter.css (debugger/src/components/PrimaryPanes/OutlineFilter.css)
-    content/debugger/src/components/PrimaryPanes/Sources.css (debugger/src/components/PrimaryPanes/Sources.css)
-    content/debugger/src/components/SecondaryPanes/Breakpoints/Breakpoints.css (debugger/src/components/SecondaryPanes/Breakpoints/Breakpoints.css)
-    content/debugger/src/components/SecondaryPanes/CommandBar.css (debugger/src/components/SecondaryPanes/CommandBar.css)
-    content/debugger/src/components/SecondaryPanes/EventListeners.css (debugger/src/components/SecondaryPanes/EventListeners.css)
-    content/debugger/src/components/SecondaryPanes/DOMMutationBreakpoints.css (debugger/src/components/SecondaryPanes/DOMMutationBreakpoints.css)
-    content/debugger/src/components/SecondaryPanes/Expressions.css (debugger/src/components/SecondaryPanes/Expressions.css)
-    content/debugger/src/components/SecondaryPanes/Frames/Frames.css (debugger/src/components/SecondaryPanes/Frames/Frames.css)
-    content/debugger/src/components/SecondaryPanes/Frames/Group.css (debugger/src/components/SecondaryPanes/Frames/Group.css)
-    content/debugger/src/components/SecondaryPanes/Scopes.css (debugger/src/components/SecondaryPanes/Scopes.css)
-    content/debugger/src/components/SecondaryPanes/SecondaryPanes.css (debugger/src/components/SecondaryPanes/SecondaryPanes.css)
-    content/debugger/src/components/SecondaryPanes/WhyPaused.css (debugger/src/components/SecondaryPanes/WhyPaused.css)
-    content/debugger/src/components/SecondaryPanes/Threads.css (debugger/src/components/SecondaryPanes/Threads.css)
-    content/debugger/src/components/SecondaryPanes/XHRBreakpoints.css (debugger/src/components/SecondaryPanes/XHRBreakpoints.css)
-    content/debugger/src/utils/editor/source-editor.css (debugger/src/utils/editor/source-editor.css)
     content/performance/index.xhtml (performance/index.xhtml)
     content/performance-new/index.xhtml (performance-new/index.xhtml)
     content/performance-new/frame-script.js (performance-new/frame-script.js)
@@ -91,70 +35,25 @@ devtools.jar:
     content/framework/browser-toolbox/window.html (framework/browser-toolbox/window.html)
     content/framework/browser-toolbox/window.css (framework/browser-toolbox/window.css)
     content/framework/browser-toolbox/window.js (framework/browser-toolbox/window.js)
-    content/framework/components/DebugTargetErrorPage.css (framework/components/DebugTargetErrorPage.css)
     content/inspector/index.xhtml (inspector/index.xhtml)
     content/shared/widgets/graphs-frame.xhtml (shared/widgets/graphs-frame.xhtml)
     content/shared/widgets/cubic-bezier.css (shared/widgets/cubic-bezier.css)
     content/shared/widgets/filter-widget.css (shared/widgets/filter-widget.css)
     content/shared/widgets/spectrum.css (shared/widgets/spectrum.css)
-    content/shared/components/SmartTrace.css (shared/components/SmartTrace.css)
-    content/shared/components/reps/reps.css (shared/components/reps/reps.css)
-    content/shared/components/tabs/Tabs.css (shared/components/tabs/Tabs.css)
-    content/shared/components/NotificationBox.css (shared/components/NotificationBox.css)
-    content/shared/components/splitter/GridElementResizer.css (shared/components/splitter/GridElementResizer.css)
-    content/shared/components/Accordion.css (shared/components/Accordion.css)
-    content/shared/components/splitter/SplitBox.css (shared/components/splitter/SplitBox.css)
-    content/shared/components/List.css (shared/components/List.css)
-    content/shared/components/tree/TreeView.css (shared/components/tree/TreeView.css)
-    content/shared/components/SidebarToggle.css (shared/components/SidebarToggle.css)
-    content/shared/components/MdnLink.css (shared/components/MdnLink.css)
     content/aboutdebugging/index.html (aboutdebugging/index.html)
     content/aboutdebugging/aboutdebugging.css (aboutdebugging/aboutdebugging.css)
-    content/aboutdebugging/src/base.css (aboutdebugging/src/base.css)
-    content/aboutdebugging/src/components/App.css (aboutdebugging/src/components/App.css)
-    content/aboutdebugging/src/components/ProfilerDialog.css (aboutdebugging/src/components/ProfilerDialog.css)
-    content/aboutdebugging/src/components/RuntimeActions.css (aboutdebugging/src/components/RuntimeActions.css)
-    content/aboutdebugging/src/components/RuntimeInfo.css (aboutdebugging/src/components/RuntimeInfo.css)
-    content/aboutdebugging/src/components/connect/ConnectPage.css (aboutdebugging/src/components/connect/ConnectPage.css)
-    content/aboutdebugging/src/components/connect/ConnectSection.css (aboutdebugging/src/components/connect/ConnectSection.css)
-    content/aboutdebugging/src/components/connect/ConnectSteps.css (aboutdebugging/src/components/connect/ConnectSteps.css)
-    content/aboutdebugging/src/components/connect/NetworkLocationsForm.css (aboutdebugging/src/components/connect/NetworkLocationsForm.css)
-    content/aboutdebugging/src/components/connect/NetworkLocationsList.css (aboutdebugging/src/components/connect/NetworkLocationsList.css)
-    content/aboutdebugging/src/components/debugtarget/DebugTargetItem.css (aboutdebugging/src/components/debugtarget/DebugTargetItem.css)
-    content/aboutdebugging/src/components/debugtarget/DebugTargetList.css (aboutdebugging/src/components/debugtarget/DebugTargetList.css)
-    content/aboutdebugging/src/components/debugtarget/DebugTargetPane.css (aboutdebugging/src/components/debugtarget/DebugTargetPane.css)
-    content/aboutdebugging/src/components/debugtarget/FieldPair.css (aboutdebugging/src/components/debugtarget/FieldPair.css)
-    content/aboutdebugging/src/components/debugtarget/ServiceWorkerAction.css (aboutdebugging/src/components/debugtarget/ServiceWorkerAction.css)
-    content/aboutdebugging/src/components/debugtarget/TemporaryExtensionInstallSection.css (aboutdebugging/src/components/debugtarget/TemporaryExtensionInstallSection.css)
-    content/aboutdebugging/src/components/shared/IconLabel.css (aboutdebugging/src/components/shared/IconLabel.css)
-    content/aboutdebugging/src/components/shared/Message.css (aboutdebugging/src/components/shared/Message.css)
-    content/aboutdebugging/src/components/sidebar/Sidebar.css (aboutdebugging/src/components/sidebar/Sidebar.css)
-    content/aboutdebugging/src/components/sidebar/SidebarFixedItem.css (aboutdebugging/src/components/sidebar/SidebarFixedItem.css)
-    content/aboutdebugging/src/components/sidebar/SidebarItem.css (aboutdebugging/src/components/sidebar/SidebarItem.css)
-    content/aboutdebugging/src/components/sidebar/SidebarRuntimeItem.css (aboutdebugging/src/components/sidebar/SidebarRuntimeItem.css)
     content/responsive/index.xhtml (responsive/index.xhtml)
     content/responsive/toolbar.xhtml (responsive/toolbar.xhtml)
-    content/responsive/index.css (responsive/index.css)
-    content/responsive/responsive-browser.css (responsive/responsive-browser.css)
-    content/responsive/images/grippers.svg (responsive/images/grippers.svg)
-    content/responsive/images/rotate-viewport.svg (responsive/images/rotate-viewport.svg)
-    content/responsive/images/touch-events.svg (responsive/images/touch-events.svg)
     content/dom/index.html (dom/index.html)
     content/dom/main.js (dom/main.js)
-    content/dom/content/dom-view.css (dom/content/dom-view.css)
     content/accessibility/index.html (accessibility/index.html)
     content/accessibility/main.js (accessibility/main.js)
-    content/accessibility/accessibility.css (accessibility/accessibility.css)
 %   skin devtools classic/1.0 %skin/
-    skin/common.css (themes/common.css)
-    skin/variables.css (themes/variables.css)
-    skin/splitters.css (themes/splitters.css)
     skin/devtools-browser.css (themes/devtools-browser.css)
     skin/dark-theme.css (themes/dark-theme.css)
     skin/light-theme.css (themes/light-theme.css)
     skin/toolbox.css (themes/toolbox.css)
     skin/tooltips.css (themes/tooltips.css)
-    skin/toolbars.css (themes/toolbars.css)
     skin/images/accessibility.svg (themes/images/accessibility.svg)
     skin/images/add.svg (themes/images/add.svg)
     skin/images/alert.svg (themes/images/alert.svg)
@@ -349,29 +248,9 @@ devtools.jar:
 
     # Application panel
     content/application/index.html (application/index.html)
-    content/application/application.css (application/application.css)
-    content/application/src/base.css (application/src/base.css)
-    content/application/src/components/App.css (application/src/components/App.css)
-    content/application/src/components/manifest/ManifestColorItem.css (application/src/components/manifest/ManifestColorItem.css)
-    content/application/src/components/manifest/ManifestIconItem.css (application/src/components/manifest/ManifestIconItem.css)
-    content/application/src/components/manifest/ManifestIssue.css (application/src/components/manifest/ManifestIssue.css)
-    content/application/src/components/manifest/ManifestIssueList.css (application/src/components/manifest/ManifestIssueList.css)
-    content/application/src/components/manifest/ManifestItem.css (application/src/components/manifest/ManifestItem.css)
-    content/application/src/components/manifest/ManifestJsonLink.css (application/src/components/manifest/ManifestJsonLink.css)
-    content/application/src/components/manifest/ManifestLoader.css (application/src/components/manifest/ManifestLoader.css)
-    content/application/src/components/manifest/ManifestSection.css (application/src/components/manifest/ManifestSection.css)
-    content/application/src/components/routing/PageSwitcher.css (application/src/components/routing/PageSwitcher.css)
-    content/application/src/components/routing/Sidebar.css (application/src/components/routing/Sidebar.css)
-    content/application/src/components/routing/SidebarItem.css (application/src/components/routing/SidebarItem.css)
-    content/application/src/components/service-workers/Registration.css (application/src/components/service-workers/Registration.css)
-    content/application/src/components/service-workers/RegistrationList.css (application/src/components/service-workers/RegistrationList.css)
-    content/application/src/components/service-workers/RegistrationListEmpty.css (application/src/components/service-workers/RegistrationListEmpty.css)
-    content/application/src/components/service-workers/Worker.css (application/src/components/service-workers/Worker.css)
-    content/application/src/components/ui/UIButton.css (application/src/components/ui/UIButton.css)
 
     # WhatsNew panel
     content/whats-new/index.html (whats-new/index.html)
-    content/whats-new/src/whats-new.css (whats-new/src/whats-new.css)
 
     # about:profiling
     skin/aboutprofiling.css (themes/aboutprofiling.css)
diff --git a/devtools/client/jsonview/converter-child.js b/devtools/client/jsonview/converter-child.js
index fa2bc3ecca39..9d1184b4b2f7 100644
--- a/devtools/client/jsonview/converter-child.js
+++ b/devtools/client/jsonview/converter-child.js
@@ -302,7 +302,7 @@ function initialHTML(doc) {
           element("link", {
             rel: "stylesheet",
             type: "text/css",
-            href: "chrome://devtools-jsonview-styles/content/main.css",
+            href: baseURI + "css/main.css",
           }),
         ]),
         element("body", {}, [
diff --git a/devtools/client/jsonview/css/main.css b/devtools/client/jsonview/css/main.css
index 996b6b7a4d86..c33258cbb3b1 100644
--- a/devtools/client/jsonview/css/main.css
+++ b/devtools/client/jsonview/css/main.css
@@ -2,12 +2,12 @@
  * 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/. */
 
-@import "chrome://devtools/skin/variables.css";
-@import "chrome://devtools/skin/common.css";
-@import "chrome://devtools/skin/toolbars.css";
+@import "resource://devtools/client/themes/variables.css";
+@import "resource://devtools/client/themes/common.css";
+@import "resource://devtools/client/themes/toolbars.css";
 
-@import "chrome://devtools/content/shared/components/tree/TreeView.css";
-@import "chrome://devtools/content/shared/components/tabs/Tabs.css";
+@import "resource://devtools/client/shared/components/tree/TreeView.css";
+@import "resource://devtools/client/shared/components/tabs/Tabs.css";
 
 @import "general.css";
 @import "search-box.css";
diff --git a/devtools/client/netmonitor/src/assets/styles/httpi.css b/devtools/client/netmonitor/src/assets/styles/httpi.css
index 88748e669d2c..ab97d0284355 100644
--- a/devtools/client/netmonitor/src/assets/styles/httpi.css
+++ b/devtools/client/netmonitor/src/assets/styles/httpi.css
@@ -3,14 +3,14 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 @import "chrome://devtools/skin/widgets.css";
-@import "chrome://devtools/content/shared/components/splitter/SplitBox.css";
-@import "chrome://devtools/content/shared/components/tree/TreeView.css";
-@import "chrome://devtools/content/shared/components/tabs/Tabs.css";
+@import "resource://devtools/client/shared/components/splitter/SplitBox.css";
+@import "resource://devtools/client/shared/components/tree/TreeView.css";
+@import "resource://devtools/client/shared/components/tabs/Tabs.css";
 @import "chrome://devtools/skin/components-frame.css";
 @import "chrome://devtools/content/shared/sourceeditor/codemirror/lib/codemirror.css";
 @import "chrome://devtools/content/shared/sourceeditor/codemirror/addon/dialog/dialog.css";
 @import "chrome://devtools/content/shared/sourceeditor/codemirror/mozilla.css";
-@import "chrome://devtools/content/shared/components/MdnLink.css";
+@import "resource://devtools/client/shared/components/MdnLink.css";
 
 /* Network panel components & styles */
 @import "chrome://devtools/content/netmonitor/src/assets/styles/variables.css";
diff --git a/devtools/client/netmonitor/src/assets/styles/netmonitor.css b/devtools/client/netmonitor/src/assets/styles/netmonitor.css
index 5ad3fe6340de..f82fabc9e651 100644
--- a/devtools/client/netmonitor/src/assets/styles/netmonitor.css
+++ b/devtools/client/netmonitor/src/assets/styles/netmonitor.css
@@ -2,16 +2,16 @@
  * 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/. */
 
-@import "chrome://devtools/content/shared/components/SidebarToggle.css";
-@import "chrome://devtools/content/shared/components/splitter/SplitBox.css";
-@import "chrome://devtools/content/shared/components/tree/TreeView.css";
-@import "chrome://devtools/content/shared/components/Accordion.css";
-@import "chrome://devtools/content/shared/components/tabs/Tabs.css";
+@import "resource://devtools/client/shared/components/SidebarToggle.css";
+@import "resource://devtools/client/shared/components/splitter/SplitBox.css";
+@import "resource://devtools/client/shared/components/tree/TreeView.css";
+@import "resource://devtools/client/shared/components/Accordion.css";
+@import "resource://devtools/client/shared/components/tabs/Tabs.css";
 @import "chrome://devtools/skin/components-frame.css";
 @import "chrome://devtools/content/shared/sourceeditor/codemirror/lib/codemirror.css";
 @import "chrome://devtools/content/shared/sourceeditor/codemirror/addon/dialog/dialog.css";
 @import "chrome://devtools/content/shared/sourceeditor/codemirror/mozilla.css";
-@import "chrome://devtools/content/shared/components/MdnLink.css";
+@import "resource://devtools/client/shared/components/MdnLink.css";
 
 /* Network panel components & styles */
 @import "chrome://devtools/content/netmonitor/src/assets/styles/variables.css";
diff --git a/devtools/client/responsive/images/moz.build b/devtools/client/responsive/images/moz.build
new file mode 100644
index 000000000000..254378eaa4ff
--- /dev/null
+++ b/devtools/client/responsive/images/moz.build
@@ -0,0 +1,11 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+DevToolsModules(
+    'grippers.svg',
+    'rotate-viewport.svg',
+    'touch-events.svg',
+)
diff --git a/devtools/client/responsive/index.css b/devtools/client/responsive/index.css
index 6fd6fd845bab..873b43bae27b 100644
--- a/devtools/client/responsive/index.css
+++ b/devtools/client/responsive/index.css
@@ -238,7 +238,7 @@ input:-moz-focusring {
 }
 
 #rotate-button::before {
-  background-image: url("chrome://devtools/content/responsive/images/rotate-viewport.svg");
+  background-image: url("./images/rotate-viewport.svg");
 }
 
 #rotate-button.viewport-orientation-landscape::before {
@@ -246,7 +246,7 @@ input:-moz-focusring {
 }
 
 #touch-simulation-button::before {
-  background-image: url("chrome://devtools/content/responsive/images/touch-events.svg");
+  background-image: url("./images/touch-events.svg");
 }
 
 #screenshot-button::before {
@@ -365,7 +365,7 @@ input:-moz-focusring {
   height: 16px;
   bottom: 0;
   right: 0;
-  background-image: url("chrome://devtools/content/responsive/images/grippers.svg");
+  background-image: url("./images/grippers.svg");
   background-position: bottom right;
   padding: 0 1px 1px 0;
   background-repeat: no-repeat;
diff --git a/devtools/client/responsive/index.xhtml b/devtools/client/responsive/index.xhtml
index 99db700e8863..3c163dd16cc8 100644
--- a/devtools/client/responsive/index.xhtml
+++ b/devtools/client/responsive/index.xhtml
@@ -7,7 +7,7 @@
   <head>
     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
     <link rel="stylesheet" type="text/css"
-          href="chrome://devtools/content/responsive/index.css"/>
+          href="resource://devtools/client/responsive/index.css"/>
     <script src="chrome://devtools/content/shared/theme-switching.js"></script>
     <script src="resource://devtools/client/responsive/index.js"></script>
   </head>
diff --git a/devtools/client/responsive/moz.build b/devtools/client/responsive/moz.build
index cc16f060f313..2ef23a95343d 100644
--- a/devtools/client/responsive/moz.build
+++ b/devtools/client/responsive/moz.build
@@ -8,15 +8,18 @@ DIRS += [
     'actions',
     'browser',
     'components',
+    'images',
     'reducers',
     'utils',
 ]
 
 DevToolsModules(
     'constants.js',
+    'index.css',
     'index.js',
     'manager.js',
     'reducers.js',
+    'responsive-browser.css',
     'store.js',
     'types.js',
     'ui.js',
diff --git a/devtools/client/responsive/toolbar.xhtml b/devtools/client/responsive/toolbar.xhtml
index 96fcb14c7f3f..cc13c4a6e141 100644
--- a/devtools/client/responsive/toolbar.xhtml
+++ b/devtools/client/responsive/toolbar.xhtml
@@ -7,7 +7,7 @@
   <head>
     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
     <link rel="stylesheet" type="text/css"
-          href="chrome://devtools/content/responsive/index.css"/>
+          href="resource://devtools/client/responsive/index.css"/>
     <script src="chrome://devtools/content/shared/theme-switching.js"></script>
     <script src="resource://devtools/client/responsive/index.js"></script>
   </head>
diff --git a/devtools/client/shared/components/moz.build b/devtools/client/shared/components/moz.build
index 7c713c752eda..18e697bf60d1 100644
--- a/devtools/client/shared/components/moz.build
+++ b/devtools/client/shared/components/moz.build
@@ -14,16 +14,22 @@ DIRS += [
 ]
 
 DevToolsModules(
+    'Accordion.css',
     'Accordion.js',
     'Frame.js',
     'HSplitBox.js',
+    'List.css',
     'List.js',
+    'MdnLink.css',
     'MdnLink.js',
+    'NotificationBox.css',
     'NotificationBox.js',
     'SearchBox.js',
     'SearchBoxAutocompletePopup.js',
     'Sidebar.js',
+    'SidebarToggle.css',
     'SidebarToggle.js',
+    'SmartTrace.css',
     'SmartTrace.js',
     'StackTrace.js',
     'VirtualizedTree.js',
diff --git a/devtools/client/shared/components/reps/moz.build b/devtools/client/shared/components/reps/moz.build
index b9c6487d7052..899b84d23dd5 100644
--- a/devtools/client/shared/components/reps/moz.build
+++ b/devtools/client/shared/components/reps/moz.build
@@ -9,5 +9,6 @@ DIRS += [
 ]
 
 DevToolsModules(
+    'reps.css',
     'reps.js',
 )
diff --git a/devtools/client/shared/components/splitter/moz.build b/devtools/client/shared/components/splitter/moz.build
index 41efbece0263..f682aaf5d3b4 100644
--- a/devtools/client/shared/components/splitter/moz.build
+++ b/devtools/client/shared/components/splitter/moz.build
@@ -6,6 +6,8 @@
 
 DevToolsModules(
     'Draggable.js',
+    'GridElementResizer.css',
     'GridElementWidthResizer.js',
+    'SplitBox.css',
     'SplitBox.js',
 )
diff --git a/devtools/client/shared/components/tabs/moz.build b/devtools/client/shared/components/tabs/moz.build
index d28fc33adfdf..8e1ae44ec7e7 100644
--- a/devtools/client/shared/components/tabs/moz.build
+++ b/devtools/client/shared/components/tabs/moz.build
@@ -6,5 +6,6 @@
 
 DevToolsModules(
     'TabBar.js',
+    'Tabs.css',
     'Tabs.js',
 )
diff --git a/devtools/client/shared/components/test/chrome/test_GridElementWidthResizer.html b/devtools/client/shared/components/test/chrome/test_GridElementWidthResizer.html
index 271169ec4477..3c02d755952b 100644
--- a/devtools/client/shared/components/test/chrome/test_GridElementWidthResizer.html
+++ b/devtools/client/shared/components/test/chrome/test_GridElementWidthResizer.html
@@ -10,8 +10,8 @@
     <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
     <script src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
     <link href="chrome://mochikit/content/tests/SimpleTest/test.css" rel="stylesheet" type="text/css"/>
-    <link href="chrome://devtools/skin/splitters.css" rel="stylesheet" type="text/css"/>
-    <link href="chrome://devtools/content/shared/components/splitter/GridElementResizer.css" rel="stylesheet" type="text/css"/>
+    <link href="resource://devtools/client/themes/splitters.css" rel="stylesheet" type="text/css"/>
+    <link href="resource://devtools/client/shared/components/splitter/GridElementResizer.css" rel="stylesheet" type="text/css"/>
     <style>
       * {
         box-sizing: border-box;
diff --git a/devtools/client/shared/components/test/chrome/test_GridElementWidthResizer_RTL.html b/devtools/client/shared/components/test/chrome/test_GridElementWidthResizer_RTL.html
index 4dfdd4c3dcf3..d4243dfd0790 100644
--- a/devtools/client/shared/components/test/chrome/test_GridElementWidthResizer_RTL.html
+++ b/devtools/client/shared/components/test/chrome/test_GridElementWidthResizer_RTL.html
@@ -10,8 +10,8 @@
     <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
     <script src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
     <link href="chrome://mochikit/content/tests/SimpleTest/test.css" rel="stylesheet" type="text/css"/>
-    <link href="chrome://devtools/skin/splitters.css" rel="stylesheet" type="text/css"/>
-    <link href="chrome://devtools/content/shared/components/splitter/GridElementResizer.css" rel="stylesheet" type="text/css"/>
+    <link href="resource://devtools/client/themes/splitters.css" rel="stylesheet" type="text/css"/>
+    <link href="resource://devtools/client/shared/components/splitter/GridElementResizer.css" rel="stylesheet" type="text/css"/>
     <style>
       * {
         box-sizing: border-box;
diff --git a/devtools/client/shared/components/test/chrome/test_HSplitBox_01.html b/devtools/client/shared/components/test/chrome/test_HSplitBox_01.html
index 09da5dac6b68..b992374ff023 100644
--- a/devtools/client/shared/components/test/chrome/test_HSplitBox_01.html
+++ b/devtools/client/shared/components/test/chrome/test_HSplitBox_01.html
@@ -12,7 +12,7 @@ Basic tests for the HSplitBox component.
   <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
   <script src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
   <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"/>
-  <link rel="stylesheet" href="chrome://devtools/skin/splitters.css" type="text/css"/>
+  <link rel="stylesheet" href="resource://devtools/client/themes/splitters.css" type="text/css"/>
   <link rel="stylesheet" href="chrome://devtools/skin/components-h-split-box.css" type="text/css"/>
   <style>
     html {
diff --git a/devtools/client/shared/components/test/chrome/test_tabs_menu.html b/devtools/client/shared/components/test/chrome/test_tabs_menu.html
index cc4638e05adf..43e530d3d5d8 100644
--- a/devtools/client/shared/components/test/chrome/test_tabs_menu.html
+++ b/devtools/client/shared/components/test/chrome/test_tabs_menu.html
@@ -11,10 +11,11 @@ Test all-tabs menu.
   <title>Tabs component All-tabs menu test</title>
   <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
   <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css">
-  <link rel="stylesheet" type="text/css" href="chrome://devtools/skin/variables.css">
-  <link rel="stylesheet" type="text/css" href="chrome://devtools/skin/common.css">
-  <link rel="stylesheet" type="text/css" href="chrome://devtools/content/shared/components/tabs/Tabs.css">
-  <link rel="stylesheet" type="text/css" href="chrome://devtools/content/inspector/components/InspectorTabPanel.css">
+  <link rel="stylesheet" type="text/css" href="resource://devtools/client/themes/variables.css">
+  <link rel="stylesheet" type="text/css" href="resource://devtools/client/themes/common.css">
+  <link rel="stylesheet" type="text/css" href="resource://devtools/client/shared/components/tabs/Tabs.css">
+  <link rel="stylesheet" type="text/css" href="resource://devtools/client/inspector/components/side-panel.css">
+  <link rel="stylesheet" type="text/css" href="resource://devtools/client/inspector/components/InspectorTabPanel.css">
 </head>
 <body>
 <pre id="test">
diff --git a/devtools/client/shared/components/test/chrome/test_tree-view_02.html b/devtools/client/shared/components/test/chrome/test_tree-view_02.html
index 77c5934a6644..dc77b2cc7a12 100644
--- a/devtools/client/shared/components/test/chrome/test_tree-view_02.html
+++ b/devtools/client/shared/components/test/chrome/test_tree-view_02.html
@@ -13,7 +13,7 @@ Test that TreeView component filtering works with keyboard.
   <script src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>
   <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css">
   <link rel="stylesheet" href="chrome://devtools/skin/light-theme.css" type="text/css">
-  <link rel="stylesheet" href="chrome://devtools/content/shared/components/tree/TreeView.css" type="text/css">
+  <link rel="stylesheet" href="resource://devtools/client/shared/components/tree/TreeView.css" type="text/css">
   <style>
     .treeRow.hide {
       display: none;
diff --git a/devtools/client/shared/components/tree/TreeView.css b/devtools/client/shared/components/tree/TreeView.css
index c641f0e15f64..b24d393de318 100644
--- a/devtools/client/shared/components/tree/TreeView.css
+++ b/devtools/client/shared/components/tree/TreeView.css
@@ -2,7 +2,7 @@
  * 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/. */
 
-@import url('chrome://devtools/content/shared/components/reps/reps.css');
+@import url('resource://devtools/client/shared/components/reps/reps.css');
 
 /******************************************************************************/
 /* TreeView Colors */
diff --git a/devtools/client/shared/components/tree/moz.build b/devtools/client/shared/components/tree/moz.build
index ba5fb1c1671d..07bb9ca96ea9 100644
--- a/devtools/client/shared/components/tree/moz.build
+++ b/devtools/client/shared/components/tree/moz.build
@@ -9,5 +9,6 @@ DevToolsModules(
     'TreeCell.js',
     'TreeHeader.js',
     'TreeRow.js',
+    'TreeView.css',
     'TreeView.js',
 )
diff --git a/devtools/client/shared/test/browser_require_raw.js b/devtools/client/shared/test/browser_require_raw.js
index a4a800ded4dd..2815bc03d33b 100644
--- a/devtools/client/shared/test/browser_require_raw.js
+++ b/devtools/client/shared/test/browser_require_raw.js
@@ -13,7 +13,7 @@ const { require: browserRequire } = BrowserLoader({
 });
 
 const variableFileContents = browserRequire(
-  "raw!chrome://devtools/skin/variables.css"
+  "raw!devtools/client/themes/variables.css"
 );
 
 function test() {
diff --git a/devtools/client/shared/test/doc_html_tooltip_hover.xhtml b/devtools/client/shared/test/doc_html_tooltip_hover.xhtml
index 27417aee8c01..ad3adc8b8deb 100644
--- a/devtools/client/shared/test/doc_html_tooltip_hover.xhtml
+++ b/devtools/client/shared/test/doc_html_tooltip_hover.xhtml
@@ -1,6 +1,6 @@
 <?xml version="1.0"?>
 <?xml-stylesheet href="chrome://global/skin/global.css"?>
-<?xml-stylesheet href="chrome://devtools/skin/variables.css"?>
+<?xml-stylesheet href="resource://devtools/client/themes/variables.css"?>
 <?xml-stylesheet href="chrome://devtools/skin/tooltips.css"?>
 <window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
  class="theme-light" title="Tooltip hover test">
diff --git a/devtools/client/shared/test/doc_inplace-editor_autocomplete_offset.xhtml b/devtools/client/shared/test/doc_inplace-editor_autocomplete_offset.xhtml
index da0ab8bc3a07..d5dba947260c 100644
--- a/devtools/client/shared/test/doc_inplace-editor_autocomplete_offset.xhtml
+++ b/devtools/client/shared/test/doc_inplace-editor_autocomplete_offset.xhtml
@@ -1,6 +1,6 @@
 <?xml version="1.0"?>
 <?xml-stylesheet href="chrome://global/skin/global.css"?>
-<?xml-stylesheet href="chrome://devtools/skin/common.css"?>
+<?xml-stylesheet href="resource://devtools/client/themes/common.css"?>
 <?xml-stylesheet href="chrome://devtools/skin/tooltips.css"?>
 <window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
  title="Tooltip test">
diff --git a/devtools/client/shared/theme.js b/devtools/client/shared/theme.js
index 4f6cba9ca598..2deb64e833ee 100644
--- a/devtools/client/shared/theme.js
+++ b/devtools/client/shared/theme.js
@@ -6,7 +6,7 @@
 
 const Services = require("Services");
 
-const variableFileContents = require("raw!chrome://devtools/skin/variables.css");
+const variableFileContents = require("theme-loader!devtools/client/themes/variables.css");
 
 const THEME_SELECTOR_STRINGS = {
   light: ":root.theme-light {",
diff --git a/devtools/client/storage/index.xhtml b/devtools/client/storage/index.xhtml
index 40f756b32b68..e1aad836aad1 100644
--- a/devtools/client/storage/index.xhtml
+++ b/devtools/client/storage/index.xhtml
@@ -6,7 +6,7 @@
 <?xml-stylesheet href="chrome://devtools/content/shared/widgets/widgets.css" type="text/css"?>
 <?xml-stylesheet href="chrome://devtools/skin/widgets.css" type="text/css"?>
 <?xml-stylesheet href="chrome://devtools/skin/storage.css" type="text/css"?>
-<?xml-stylesheet href="chrome://devtools/content/shared/components/SidebarToggle.css" type="text/css"?>
+<?xml-stylesheet href="resource://devtools/client/shared/components/SidebarToggle.css" type="text/css"?>
 
 <!DOCTYPE window [
   <!ENTITY % storageDTD SYSTEM "chrome://devtools/locale/storage.dtd">
diff --git a/devtools/client/themes/common.css b/devtools/client/themes/common.css
index 4dc0e4e5e3fa..56a84ab4f34f 100644
--- a/devtools/client/themes/common.css
+++ b/devtools/client/themes/common.css
@@ -2,7 +2,7 @@
  * 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/. */
 
-@import url("chrome://devtools/skin/splitters.css");
+@import url("resource://devtools/client/themes/splitters.css");
 @namespace html url("http://www.w3.org/1999/xhtml");
 
 :root {
diff --git a/devtools/client/themes/dark-theme.css b/devtools/client/themes/dark-theme.css
index f8ac8beb2df0..ef66efec0bc0 100644
--- a/devtools/client/themes/dark-theme.css
+++ b/devtools/client/themes/dark-theme.css
@@ -2,9 +2,9 @@
  * 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/. */
 
-@import url(chrome://devtools/skin/variables.css);
-@import url(chrome://devtools/skin/common.css);
-@import url(chrome://devtools/skin/toolbars.css);
+@import url(resource://devtools/client/themes/variables.css);
+@import url(resource://devtools/client/themes/common.css);
+@import url(resource://devtools/client/themes/toolbars.css);
 @import url(chrome://devtools/skin/tooltips.css);
 
 body {
diff --git a/devtools/client/themes/devtools-browser.css b/devtools/client/themes/devtools-browser.css
index bc208e3bc85b..0dbb3fda16e4 100644
--- a/devtools/client/themes/devtools-browser.css
+++ b/devtools/client/themes/devtools-browser.css
@@ -2,10 +2,10 @@
  * 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/. */
 
-@import url("chrome://devtools/skin/splitters.css");
+@import url("resource://devtools/client/themes/splitters.css");
 /* Imports the styles that will apply to the browser window for Responsive Design Mode.
    This is dynamically loaded when either the toolbox or RDM is open. */
-@import url("chrome://devtools/content/responsive/responsive-browser.css");
+@import url("resource://devtools/client/responsive/responsive-browser.css");
 
 /* Set min-height to 29px as it matches the height of the .devtools-tabbar (/devtools/client/themes/toolbox.css#67)
  * This prevents the shrinking of the toolbox until it disappears. */
diff --git a/devtools/client/themes/light-theme.css b/devtools/client/themes/light-theme.css
index d19b91143a59..d86cef85e2d8 100644
--- a/devtools/client/themes/light-theme.css
+++ b/devtools/client/themes/light-theme.css
@@ -2,9 +2,9 @@
  * 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/. */
 
-@import url(chrome://devtools/skin/variables.css);
-@import url(chrome://devtools/skin/common.css);
-@import url(chrome://devtools/skin/toolbars.css);
+@import url(resource://devtools/client/themes/variables.css);
+@import url(resource://devtools/client/themes/common.css);
+@import url(resource://devtools/client/themes/toolbars.css);
 @import url(chrome://devtools/skin/tooltips.css);
 
 body {
diff --git a/devtools/client/themes/moz.build b/devtools/client/themes/moz.build
index 99665d5b4bc8..543f4eff0411 100644
--- a/devtools/client/themes/moz.build
+++ b/devtools/client/themes/moz.build
@@ -7,3 +7,10 @@
 DIRS += [
     'audio',
 ]
+
+DevToolsModules(
+    'common.css',
+    'splitters.css',
+    'toolbars.css',
+    'variables.css',
+)
diff --git a/devtools/client/webconsole/components/Input/moz.build b/devtools/client/webconsole/components/Input/moz.build
index 696cded907c8..187bd1c9f98f 100644
--- a/devtools/client/webconsole/components/Input/moz.build
+++ b/devtools/client/webconsole/components/Input/moz.build
@@ -5,9 +5,12 @@
 
 DevToolsModules(
     'ConfirmDialog.js',
+    'EagerEvaluation.css',
     'EagerEvaluation.js',
     'EditorToolbar.js',
+    'EvaluationContextSelector.css',
     'EvaluationContextSelector.js',
     'JSTerm.js',
+    'ReverseSearchInput.css',
     'ReverseSearchInput.js',
 )
diff --git a/devtools/client/webconsole/components/moz.build b/devtools/client/webconsole/components/moz.build
index 37c741b75054..e965853484d8 100644
--- a/devtools/client/webconsole/components/moz.build
+++ b/devtools/client/webconsole/components/moz.build
@@ -10,6 +10,7 @@ DIRS += [
 ]
 
 DevToolsModules(
+    'App.css',
     'App.js',
     'SideBar.js',
 )
diff --git a/devtools/client/webconsole/index.html b/devtools/client/webconsole/index.html
index 38eeacb5e2f1..979d473a21af 100644
--- a/devtools/client/webconsole/index.html
+++ b/devtools/client/webconsole/index.html
@@ -14,17 +14,17 @@
     <link rel="stylesheet" href="chrome://devtools/skin/widgets.css"/>
     <link rel="stylesheet" href="chrome://devtools/skin/webconsole.css"/>
     <link rel="stylesheet" href="chrome://devtools/skin/components-frame.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/shared/components/SmartTrace.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/shared/components/reps/reps.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/shared/components/tabs/Tabs.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/shared/components/NotificationBox.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/shared/components/splitter/GridElementResizer.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/shared/components/SmartTrace.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/shared/components/reps/reps.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/shared/components/tabs/Tabs.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/shared/components/NotificationBox.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/shared/components/splitter/GridElementResizer.css"/>
     <link rel="stylesheet" href="chrome://devtools/content/netmonitor/src/assets/styles/httpi.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/webconsole/components/Input/EagerEvaluation.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/webconsole/components/Input/EvaluationContextSelector.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/webconsole/components/Input/ReverseSearchInput.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/webconsole/components/App.css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/shared/components/Accordion.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/webconsole/components/Input/EagerEvaluation.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/webconsole/components/Input/EvaluationContextSelector.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/webconsole/components/Input/ReverseSearchInput.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/webconsole/components/App.css"/>
+    <link rel="stylesheet" href="resource://devtools/client/shared/components/Accordion.css"/>
     <link rel="stylesheet" href="chrome://devtools/content/netmonitor/src/assets/styles/StatusCode.css"/>
     <link rel="stylesheet" href="chrome://devtools/content/netmonitor/src/assets/styles/RequestList.css"/>
     <link rel="stylesheet" href="chrome://devtools/content/netmonitor/src/assets/styles/UrlPreview.css" />
diff --git a/devtools/client/whats-new/index.html b/devtools/client/whats-new/index.html
index fd77cd8b4bb7..6ac98235b7e4 100644
--- a/devtools/client/whats-new/index.html
+++ b/devtools/client/whats-new/index.html
@@ -4,7 +4,7 @@
 <!DOCTYPE html>
 <html dir="">
 <head>
-  <link rel="stylesheet" href="chrome://devtools/content/whats-new/src/whats-new.css"/>
+  <link rel="stylesheet" href="resource://devtools/client/whats-new/src/whats-new.css"/>
   <script src="chrome://devtools/content/shared/theme-switching.js"></script>
 </head>
 
diff --git a/devtools/client/whats-new/src/moz.build b/devtools/client/whats-new/src/moz.build
index 8c16f3b44ecd..fd1699278edd 100644
--- a/devtools/client/whats-new/src/moz.build
+++ b/devtools/client/whats-new/src/moz.build
@@ -4,4 +4,5 @@
 
 DevToolsModules(
     'main.js',
+    'whats-new.css'
 )
diff --git a/devtools/shared/jar.mn b/devtools/shared/jar.mn
index 4a32cae8ce33..8992bc36aa3b 100644
--- a/devtools/shared/jar.mn
+++ b/devtools/shared/jar.mn
@@ -8,7 +8,6 @@ devtools.jar:
 %   resource devtools %modules/devtools/
 %   resource devtools-client-jsonview resource://devtools/client/jsonview/ contentaccessible=yes
 %   resource devtools-client-shared resource://devtools/client/shared/ contentaccessible=yes
-%   content devtools-jsonview-styles %modules/devtools/client/jsonview/css/ contentaccessible=yes
 # The typical approach would be to list all the resource files in this manifest
 # for installation.  Instead of doing this, use the DevToolsModules syntax via
 # moz.build files to do the installation so that we can enforce correct paths
diff --git a/devtools/shared/tests/xpcshell/test_require_raw.js b/devtools/shared/tests/xpcshell/test_require_raw.js
index bd8be2f94f0a..75031ec33d9c 100644
--- a/devtools/shared/tests/xpcshell/test_require_raw.js
+++ b/devtools/shared/tests/xpcshell/test_require_raw.js
@@ -9,7 +9,7 @@ function run_test() {
   const loader = new DevToolsLoader();
   const require = loader.require;
 
-  const variableFileContents = require("raw!chrome://devtools/skin/variables.css");
+  const variableFileContents = require("raw!devtools/client/themes/variables.css");
   ok(variableFileContents.length > 0, "raw browserRequire worked");
 
   const propertiesFileContents = require("raw!devtools/client/locales/shared.properties");