Hello,
@User547952 : this key does not belong to Mozilla Firefox only. Mozilla Firefox creates this key only for a limited time (the current session). However, we target the same key created by several malwares, which is not deleted when the current session is terminated.
It's a corner case, but we'll look deeper to see what we can do about that..
Best regards,
fr33tux, 2016-05-06 18:45:56...