I don't know how to edit or delete my previous post. I wanted to correct it but I can't, so I'm sorry but below I am sending it again but corrected:
Hello,
I worked at the computer on the night of July 9-10.
I turned on Firefox and it happened the same. I was able to check that Firefox has updated to version 78.0.2.
Maybe it has something to do with something it contains, e.g. something related to security.
Here is it description: https://www.mozilla.org/en-US/firefox/78.0.2/releasenotes/
Just like the @frozen user, I have a profile on drive 😧 However, I have installed Firefox and Malwarebytes Premium (like @frozen in version 4.1.0.56) long time ago, I haven't changed anything in add-ons in Firefox for a long time, and this problem has not yet appeared until now (@frozen's problem appeared already in April).
Below is a report from Malewarebytes:
I read posts written by @frozen. Therefore, I'm afraid of the next update from Firefox.