Hello,

Try Firefox Safe Mode to see if the problem goes away. Firefox Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes).

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu:

• Click the menu button , click Help and select Restart with Add-ons Disabled.

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)

When the Firefox Safe Mode window appears, select "Start in Safe Mode".

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, theme, or hardware acceleration. Please follow the steps in 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.

guigs said

Hello, Try Firefox Safe Mode to see if the problem goes away. Firefox Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes). If Firefox is open, you can restart in Firefox Safe Mode from the Help menu:

• Click the menu button , click Help and select Restart with Add-ons Disabled.

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)

When the Firefox Safe Mode window appears, select "Start in Safe Mode".

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, theme, or hardware acceleration. Please follow the steps in 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.

Already did that, i deleted profile from appdata folder, and synced account. Problem still occurs. Im on windows 10 x64. Problem is showing up on both 32 and 64 bit version.

Ok no problem, let's see what else we can do. If it does not also happen in another browser, my first gut would be its a compatibility issue, especially if it was working before the update. The developer reference is below if you know the site developer.

• https://developer.mozilla.org/en-US/F.../43

Else webcompat.com is where we report the issues.

Since it did not make a difference in safe mode, its not hardware acceleration. In each of the different installs, were you using the same profile?

• Profile Manager - Create, remove or switch Firefox profiles

guigs said

Ok no problem, let's see what else we can do. If it does not also happen in another browser, my first gut would be its a compatibility issue, especially if it was working before the update. The developer reference is below if you know the site developer.

• https://developer.mozilla.org/en-US/F.../43

Else webcompat.com is where we report the issues. Since it did not make a difference in safe mode, its not hardware acceleration. In each of the different installs, were you using the same profile?

• Profile Manager - Create, remove or switch Firefox profiles

Ill test developper version. I noticed that happens sometimes without visiting mentioned site.

Creating new profile doesn't help in regular firefox versions. No matter if i use profile manager of just delete mozilla folder from app data, effect is same.