Hello,

Try Firefox Safe Mode to see if the problem goes away. 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.

When you figure out what's causing your issues, please let us know. It might help others with the same problem.

Thank you.

Thanks, jayakumars: In the interim, the problem seems to have corrected itself. I am not noticing any lag at this time. I did indeed start in safemode per instructions and surfed briefly. I noticed no lag whatever. But as I said the lag appears to have corrected itself prior to the safemode check. Some other events in the interim were an Adobe flashplayer update right at boot up. I have Java and Adobe set to auto update with alert, as well as Windows. So. Thanks both for your time and your surprisingly prompt reply. I am sure there are others with real workability issues. Best Regards, mitcorb

Safe mode is better, but there are still some jumps, windows temporarily resize (2nd scroll bar appears), etc. Something is definitely funny. Thanks.