Issue 242 - Use user style sheets on Chromium

lib/cssInjection.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 /** @module cssInjection */
 
 "use strict";
 
 const {RegExpFilter} = require("filterClasses");
 const {ElemHide} = require("elemHide");
 const {ElemHideEmulation} = require("elemHideEmulation");
 const {checkWhitelisted} = require("whitelisting");
 const {extractHostFromFrame} = require("url");
 const {port} = require("messaging");
 const devtools = require("devtools");
+const info = require("info");
 
-const userStyleSheetsSupported = "extensionTypes" in browser &&
-                                 "CSSOrigin" in browser.extensionTypes;
+const cssOriginSupported = "extensionTypes" in browser &&
+                           "CSSOrigin" in browser.extensionTypes;
+const userStyleSheetsSupported = cssOriginSupported ||
+                                 (info.platform == "chromium" &&
+                                  parseInt(info.platformVersion, 10) >= 64);
 
 function hideElements(tabId, frameId, selectors)
 {
-  browser.tabs.insertCSS(tabId, {
+  let options = {
     code: selectors.join(", ") + "{display: none !important;}",
-    cssOrigin: "user",
     frameId,
     matchAboutBlank: true,
     runAt: "document_start"
-  });
+  };
+
+  if (cssOriginSupported)
+    options.cssOrigin = "user";
+
+  browser.tabs.insertCSS(tabId, options);
 }
 
 port.on("elemhide.getSelectors", (msg, sender) =>
 {
   let selectors = [];
   let emulatedPatterns = [];
   let trace = devtools && devtools.hasPanel(sender.page);
   let inject = !userStyleSheetsSupported;
 
   if (!checkWhitelisted(sender.page, sender.frame,
@@ skipping 20 matching lines @@
   if (trace || inject)
     response.selectors = selectors;
 
   return response;
 });
 
 port.on("elemhide.injectSelectors", (msg, sender) =>
 {
   hideElements(sender.page.id, sender.frame.id, msg.selectors);
 });