Issue 5864 - Remove previous style sheet before adding one

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
@@ skipping 25 matching lines @@
     code: styleSheet,
     cssOrigin: "user",
     frameId,
     matchAboutBlank: true,
     runAt: "document_start"
   });
 }
 
 function removeStyleSheet(tabId, frameId, styleSheet)
 {
-  chrome.tabs.removeCSS(tabId, {
+  browser.tabs.removeCSS(tabId, {
     code: styleSheet,
     cssOrigin: "user",
     frameId,
     matchAboutBlank: true
   });
 }
 
-function updateFrameStyles(pageId, frameId, selectors, groupName)
+function updateFrameStyles(tabId, frameId, selectors, groupName)
 {
   let styleSheet = null;
   if (selectors.length > 0)
     styleSheet = selectors.join(", ") + "{display: none !important;}";
 
-  let frame = ext.getFrame(pageId, frameId);
+  let frame = ext.getFrame(tabId, frameId);
   if (!frame.injectedStyleSheets)
     frame.injectedStyleSheets = new Map();
 
   let oldStyleSheet = frame.injectedStyleSheets.get(groupName);
 
   // Ideally we would compare the old and new style sheets and skip this code
   // if they're the same, but the old style sheet can be a leftover from a
   // previous instance of the frame. We must add the new style sheet
   // regardless.
 
@@ skipping 43 matching lines @@
     response.selectors = selectors;
 
   return response;
 });
 
 port.on("elemhide.injectSelectors", (message, sender) =>
 {
   updateFrameStyles(sender.page.id, sender.frame.id, message.selectors,
                     message.groupName);
 });