Which extension is causing a problem
I used safe mode to find out if an extension was causing a problem. In safe mode there was no problem. I searched for the extension that is causing it. I went into 'troubleshoot information" for the list of installed extensions but there was no way to disable or remove any of them to find the cause. (The list of extensions in the settings menu showed only one extension and 2 pre-intalled plug ins)
Alla svar (3)
Can you give more detail on what problems you have as Troubleshoot Mode does more than disabling extensions ?
The System Details only show the default built-in search engines and one disabled normal extension, so an extension doesn't look like a porblem.
With safe mode on, the video problem (black screen with Facebook videos) goes away. But using safe mode every time I want to go to Facebook is, so far, the only way to proceed. There must be another way. And I don't have this problem with either Chrome or Edge.
Ändrad
You can try to disable hardware acceleration in Firefox.
- Settings -> General -> Performance
remove checkmark: [ ] "Use recommended performance settings"
remove checkmark: [ ] "Use hardware acceleration when available" - https://support.mozilla.org/en-US/kb/performance-settings
Close and restart Firefox after modifying the setting to make changes effective.
You can check if there is an update for your graphics display driver and check for hardware acceleration related issues.