Tap here to go to the mobile version of the site.
Your Firefox is out of date and may contain a security risk! Upgrade Firefox

Support Forum

Firefox is very slow and laggy for most websites I visit, cannot figure out how to fix.


This started just about a month or so ago. Almost every website I visit Firefox either lags or outright stalls, giving me the (unresponsive) notice at the top or unresponsive script error messages.

I have tried every suggestion I could find in the help, including "Firefox uses too much resources", "Firefox hangs or is unresponsive", and "Unresponsive script - how to fix". I have cleared all history, cookies and cache, reset Firefox, reinstalled, everything I can. I disabled all my extensions and add-ons one by one to see if they impacted, I made sure everything including Firefox is up to date. Nothing has changed the behavior.

Any help here would be appreciated.

Post a Reply

Additional System Details

Installed Plug-ins

  • Shockwave Flash 12.0 r0
  • Adobe PDF Plug-In For Firefox and Netscape 11.0.06
  • Next Generation Java Plug-in 10.51.2 for Mozilla browsers
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Google Update
  • Adobe Shockwave for Director Netscape plug-in, version
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.


  • User Agent: Mozilla/5.0 (Windows NT 6.1; rv:26.0) Gecko/20100101 Firefox/26.0

More Information

I am posting from a different computer, so cannot provide these details at the moment. I will update when I get a chance to log in from home.

  • Top 25 Contributor
529 solutions 5045 answers

Chosen Solution

How about a whole new profile?

SEE: Use the Profile Manager to create and remove Firefox profiles

Was this helpful to you? 4
  • Top 10 Contributor
  • Moderator
10762 solutions 96861 answers

It is possible that your security software (firewall, anti-virus) blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.


Was this helpful to you? 3

Helpful Reply

That solved it. I created a new profile and that seems to fix the problem. Everything loads quickly again, no lag.

I guess I will transfer over my bookmarks to the new profile and delete the old one. Thank you for your help.

Was this helpful to you? 6
Ask a question

You must log in to your account to reply to posts. Please start a new question, if you do not have an account yet.