Thanks in advance.

Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes). If the problem goes away, that tells us one thing. If it does not, that tells us something else.

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Restart Firefox. Are there any problems?

It was already disabled.

Thanks

What theme are you using? Switch to the default.

Already there.

Thanks again.

Hello,

I am glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution more easily.

Thank you for contacting Mozilla Support.

The problem was magically solved.

I didn't do anything from what you suggest above, the program was already set with these settings.

Thanks anyway

It could have been a corrupt file that was overwritten.

Note that you can try these steps in case of issues with web pages:

You can reload web page(s) and bypass the cache to refresh possibly outdated or corrupted files.

• Hold down the Shift key and left-click the Reload button
• Press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
• Press "Command + Shift + R" (Mac)

Clear the cache and remove cookies only from websites that cause problems.

"Clear the Cache":

• Firefox/Tools > Options > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems:

• Firefox/Tools > Options > Privacy > "Use custom settings for history" > Cookies: "Show Cookies"

See also:

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

I didn't realize it but in the meantime I cleaned the cookies and the cache.

Thanks a lot

Glad to help. Safe Surfing.

The problem occurred again.

I refreshed the browser and tried to figure out if an add-on installation is faulty by installing them one by one while checking the site. In the beginning, everything was working perfectly.

Now, the problem takes place again.

I am using the following add-ons: Ghostery, AdBlock Plus, HTTPS-Everywhere, Download status bar, Super Start and New Tab Homepage.

Thanks again

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Restart Firefox. Are there any problems?

Disable one add-on for a few days as a test. After, disable a different one.