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I am getting a message that says something about Script: resource:///components/nsBlocklistService.js:756 Does anyone know what this is?


When I open Firefox I get a message that says something about a script not working on the page... Script: resource:///components/nsBlocklistService.js:756 and do I want to continue. Does anyone know what this is?

Additional System Details

This happened

Just once or twice

This started when...

a few days ago

Installed Plug-ins

  • GEPlugin
  • Google Update
  • Adobe PDF Plug-In For Firefox and Netscape 10.1.2
  • Shockwave Flash 11.1 r102
  • np-mswmp
  • 5.0.61118.0
  • DivX VOD Helper Plug-in
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Next Generation Java Plug-in 1.6.0_24 for Mozilla browsers
  • RealJukebox Netscape Plugin
  • RealPlayer(tm) HTML5VideoShim Plug-In
  • RealPlayer(tm) LiveConnect-Enabled Plug-In
  • Provides additional functionality on Facebook. See our web site for details.
  • Windows Presentation Foundation (WPF) plug-in for Mozilla browsers
  • DRM Netscape Network Object
  • DRM Store Netscape Plugin
  • Npdsplay dll


  • User Agent: Mozilla/5.0 (Windows NT 5.1; rv:9.0.1) Gecko/20100101 Firefox/9.0.1

More Information

Oxylatium 44 solutions 273 answers

Helpful Reply

Surely a broken add-on or script. Restsart Firefox in safe mode and check if the issue is still here. If it's not present, find the culprit add-on.

Modified by Oxylatium

  • Top 10 Contributor
  • Moderator
10738 solutions 96600 answers

Helpful Reply

That is the JavaScript that deals with block listing in Firefox.
This line seems to be about testing for blocked plugins.

Start Firefox in Troubleshoot Firefox issues using Safe Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).