Issue 5347 - Do not show composer menu item on Firefox for Android

lib/filterComposer.js

Index: lib/filterComposer.js
===================================================================
--- a/lib/filterComposer.js
+++ b/lib/filterComposer.js
@@ -21,16 +21,17 @@
 
 const {defaultMatcher} = require("matcher");
 const {RegExpFilter} = require("filterClasses");
 const {FilterNotifier} = require("filterNotifier");
 const {Prefs} = require("prefs");
 const {extractHostFromFrame, stringifyURL, isThirdParty} = require("url");
 const {getKey, checkWhitelisted} = require("whitelisting");
 const {port} = require("messaging");
+const info = require("info");
 
 let readyPages = new ext.PageMap();
 
 /**
  * Checks whether the given page is ready to use the filter composer
  *
  * @param {Page} page
  * @return {boolean}
@@ -175,18 +176,24 @@
 };
 
 function updateContextMenu(page, filter)
 {
   page.contextMenus.remove(contextMenuItem);
 
   if (typeof filter == "undefined")
     filter = checkWhitelisted(page);
-  if (!filter && Prefs.shouldShowBlockElementMenu && readyPages.has(page))
+
+  // We don't support the filter composer on Firefox for Android, because the
+  // user experience on mobile is quite different.
+  if (info.application != "fennec" &&
+      !filter && Prefs.shouldShowBlockElementMenu && readyPages.has(page))
+  {
     page.contextMenus.create(contextMenuItem);
+  }
 }
 
 FilterNotifier.on("page.WhitelistingStateRevalidate", updateContextMenu);
 
 Prefs.on("shouldShowBlockElementMenu", () =>
 {
   ext.pages.query({}, pages =>
   {