1 files changed, 45 insertions, 0 deletions
diff --git a/browser/base/content/browser-uacompat.js b/browser/base/content/browser-uacompat.js
new file mode 100644
index 000000000..933aa55d1
--- /dev/null
+++ b/browser/base/content/browser-uacompat.js
@@ -0,0 +1,45 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+var UserAgentCompatibility = {
+  PREF_UA_COMPAT: "general.useragent.compatMode",
+  PREF_UA_COMPAT_GECKO: "general.useragent.compatMode.gecko",
+  PREF_UA_COMPAT_FIREFOX: "general.useragent.compatMode.firefox",
+  
+  init: function() {
+    this.checkPreferences();
+    Services.prefs.addObserver(this.PREF_UA_COMPAT, this, false);
+    Services.prefs.addObserver(this.PREF_UA_COMPAT_GECKO, this, false);
+    Services.prefs.addObserver(this.PREF_UA_COMPAT_FIREFOX, this, false);
+  },
+
+  uninit: function() {
+    Services.prefs.removeObserver(this.PREF_UA_COMPAT, this, false);
+    Services.prefs.removeObserver(this.PREF_UA_COMPAT_GECKO, this, false);
+    Services.prefs.removeObserver(this.PREF_UA_COMPAT_FIREFOX, this, false);
+  },
+
+  observe: function() {
+    this.checkPreferences();
+  },
+  
+  checkPreferences: function() {
+    var compatMode = Services.prefs.getIntPref(this.PREF_UA_COMPAT);
+    
+    switch(compatMode) {
+      case 0:
+        Services.prefs.setBoolPref(this.PREF_UA_COMPAT_GECKO, false);
+        Services.prefs.setBoolPref(this.PREF_UA_COMPAT_FIREFOX, false);
+        break;
+      case 1:
+        Services.prefs.setBoolPref(this.PREF_UA_COMPAT_GECKO, true);
+        Services.prefs.setBoolPref(this.PREF_UA_COMPAT_FIREFOX, false);
+        break;
+      case 2:
+        Services.prefs.setBoolPref(this.PREF_UA_COMPAT_GECKO, true);
+        Services.prefs.setBoolPref(this.PREF_UA_COMPAT_FIREFOX, true);
+        break;
+    }
+  }
+};