Comment 2 for bug 1295826

You're probably right, but this should still probably be handled better. I don't want to whitelist the entire .cache/mozilla path - under most circumstances, I do want Bleachbit to clean it. Even if Firefox files are in .cache/mozilla, I'd prefer them to be controlled by the Firefox option rather than the System cache option.

But under no circumstances should Bleachbit be deleting Firefox-related files while Firefox is actively running! At the very least, it ought to check whether a process named "firefox" is running and, if it is, refuse to delete any files with "firefox" or "mozilla" in the path (and likewise for Thunderbird).