| Index: chrome/content/ui/sidebar.js | 
| =================================================================== | 
| --- a/chrome/content/ui/sidebar.js | 
| +++ b/chrome/content/ui/sidebar.js | 
| @@ -80,17 +80,17 @@ function init() { | 
|  | 
| let wnd = parent.document.documentElement; | 
| for (let attr in defaults) | 
| if (!wnd.hasAttribute(attr)) | 
| wnd.setAttribute(attr, defaults[attr]); | 
| } | 
|  | 
| let {getBrowser, addBrowserLocationListener} = require("appSupport"); | 
| -  window.__defineGetter__("content", function() {return getBrowser(mainWin).contentWindow;}); | 
| +  Object.defineProperty(window, "content", { get: () => getBrowser(mainWin).contentWindow }); | 
|  | 
| // Initialize matcher for disabled filters | 
| reloadDisabledFilters(); | 
| FilterNotifier.addListener(reloadDisabledFilters); | 
| Prefs.addListener(onPrefChange); | 
|  | 
| // Activate flasher | 
| list.addEventListener("select", onSelectionChange, false); | 
|  |