I agree. Firefox does some weird things occasionally. Always figure it's because I've missed some setting or update or add-on or ... However, right now, it is working fine on both PC and laptop.

An issue I was experiencing with no sound on videos - which drove me to Chrome for several days - was easily corrected when I searched the Lounge and found this advice: ensure Firefox was not muted in the audio mixer. Well, duh, I checked and found that it had somehow been muted and unmuting it with a check corrected the issue.

Wish I could give you more specific technical help, elikam because I share your desire to stick with Firefox! Good luck.