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firefox.cfg no longer overwrite new tab content

  • 4 replies
  • 4 have this problem
  • 710 views
  • Last reply by sie103

I'm using firefox developer edition. The latest version: 76.0b2 I have firefox.cfg set up to overwrite new tab content with locally stored html. The code in firefox.cfg that worked until recent update:

/* set new tab page */ try {

 var newTabURL = "file:///G:/Documents/Newtab.html";
 aboutNewTabService = Cc["@mozilla.org/browser/aboutnewtab-service;1"].getService(Ci.nsIAboutNewTabService);
 aboutNewTabService.newTabURL = newTabURL;

} catch(e){Cu.reportError(e);} // report errors in the Browser Console

In the browser console there is an error message displayed:

[Exception... "Cannot modify properties of a WrappedNative" nsresult: "0x80570034 (NS_ERROR_XPC_CANT_MODIFY_PROP_ON_WN)" location: "JS frame :: firefox.cfg :: <TOP_LEVEL> :: line 7" data: no]

Any idea what that error message means and how to resolve it? Does anything changed regarding new tab overwrite?

I'm using firefox developer edition. The latest version: 76.0b2 I have firefox.cfg set up to overwrite new tab content with locally stored html. The code in firefox.cfg that worked until recent update: /* set new tab page */ try { var newTabURL = "file:///G:/Documents/Newtab.html"; aboutNewTabService = Cc["@mozilla.org/browser/aboutnewtab-service;1"].getService(Ci.nsIAboutNewTabService); aboutNewTabService.newTabURL = newTabURL; } catch(e){Cu.reportError(e);} // report errors in the Browser Console In the browser console there is an error message displayed: [Exception... "Cannot modify properties of a WrappedNative" nsresult: "0x80570034 (NS_ERROR_XPC_CANT_MODIFY_PROP_ON_WN)" location: "JS frame :: firefox.cfg :: <TOP_LEVEL> :: line 7" data: no] Any idea what that error message means and how to resolve it? Does anything changed regarding new tab overwrite?

Chosen solution

Try this code:

//
var {classes:Cc,interfaces:Ci,utils:Cu} = Components;

/* set new tab page */
try {
  Cu.import("resource:///modules/AboutNewTab.jsm");
  var newTabURL = "file:///G:/Documents/Newtab.html";
  AboutNewTab.newTabURL = newTabURL;
} catch(e){Cu.reportError(e);} // report errors in the Browser Console
Read this answer in context 👍 3

All Replies (4)

Chosen Solution

Try this code:

//
var {classes:Cc,interfaces:Ci,utils:Cu} = Components;

/* set new tab page */
try {
  Cu.import("resource:///modules/AboutNewTab.jsm");
  var newTabURL = "file:///G:/Documents/Newtab.html";
  AboutNewTab.newTabURL = newTabURL;
} catch(e){Cu.reportError(e);} // report errors in the Browser Console

Modified by cor-el

Thank You SO MUCH! This works!

Is there any way to take focus from the address bar? My local page has a search field on it.

This code takes the focus away from the address bar:

// var {classes:Cc,interfaces:Ci,utils:Cu} = Components; try {

 Cu.import("resource:///modules/AboutNewTab.jsm");  
 var newTabURL = "file:///D:/Dox/Startseite/Startseite.htm";  
 AboutNewTab.newTabURL = newTabURL;  

} catch(e){Cu.reportError(e);} // report errors in the Browser Console

// Optional: Don't place the caret in the location bar. Useful if you want a page's search box to have focus instead. function SetFocusOnPage () {

 setTimeout(function() {
 gBrowser.selectedBrowser.focus();
 }, 0);

} gBrowser.tabContainer.addEventListener("TabOpen", SetFocusOnPage, false);