Please check if all your plugins are up-to-date. To do this, go to the Mozilla Plugin Check site.

Once you're there, the site will check if all your plugins have the latest versions. If you see plugins in the list that have a yellow Update button or a red Update now button, please update these immediately.

To do so, please click each red or yellow button. Then you should see a site that allows you to download the latest version. Double-click the downloaded file to start the installation and follow the steps mentioned in the installation procedure.

Thanks, However Windows Presentation Foundation seemed to be the only plugin. Are there others I need to get Google groups to work? Peter

Any other ideas? Is Firefox not compatible with google groups? Thanks for any advice. Peter

Sorry for the delay in my response.

I know that some features of Google are not compatible with other browsers, but those are mostly features in Gmail and Google Drive. You should still be able to access your Google group.

There is the chance that an add-on or plugin installed in Firefox is causing the issue. To find out, you can try Firefox's Safe Mode.

Firefox Safe Mode is a troubleshooting mode that turns off some settings and disables most add-ons (extensions and themes).

(If you're using an added theme, switch to the Default theme.)

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu by clicking on the Restart with Add-ons Disabled... menu item:


If Firefox is not running, you can start Firefox in Safe Mode as follows:

• On Windows: Hold the Shift key when you open the Firefox desktop or Start menu shortcut.
• On Mac: Hold the option key while starting Firefox.
• On Linux: Quit Firefox, go to your Terminal and run firefox -safe-mode
  (you may need to specify the Firefox installation path e.g. /usr/lib/firefox)

Once you get the pop-up, just select "'Start in Safe Mode"

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to find the cause.

To exit Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

Please report back soon.