CCleaner a resource hog that stops computer

[User48]

I've seen some comments that this is a frefox issue - but "As of September 2019, Firefox was the second-most widely used desktop browser, and that position makes it the third-most popular with approximately 4.44% of worldwide usage share of web browsers across all platforms."  Wikipedia.  So ccleaner should accommodate firefox, rather than the other way around.

[Andavari]

Perhaps that's what Nergal's comment was about without elaborating, and perhaps unticking/disabling under Firefox: Compact Databases would be a worthy test to see if it remedies the issue.

Although, CCleaner very rarely actually compacts the Firefox databases ("SQLite files").

[Dave CCleaner]

9 hours ago, Andavari said:

This is that other post that I wasn't able to find earlier, with tons of CCleaner.exe files started as shown in Task Manager, although that isn't what this topic is about:

 

Indeed.  That was the CCleaner update process jamming in an issue that was specific to the old CCleaner 5.44 (about 18 version ago).  And also a reason for asking for the Task Manager dump screenshot - amongst other things it can provide an indication as to whether it is CCleaner itself causing the problem for you or if there is an ancillary service which is having problems.