Isn't this a missed opportunity for AVAST to promote the use of CCleaner which seems to get rid of such TMP browser files by default? I certainly do not have anything similar in the location described and I use that at the end of every day so I'm assuming it is one of the things it 'cleans'. I actually have an, empty, AVAST folder there in the Local folder
Even if it does not do that by default and this is something specific to the OP's system/browser version/OS CCleaner has the Settings options to include custom locations like that.
I've just done a bit of research and
BCL apparently means Browser Cleanup List and the 'problem' described has been reported at least for the last 5 years including this very forum:-
https://forum.avast.com/index.php?topic=148479.0There is some really unhelpful advice about this you can find even at otherwise reliable places like the Malwarebytes' and other Anti-Virus forums. But that ^ topic suggests it may simply be a backup copy, made for safety/restore reasons, of your browser profile settings etc made by the AVAST Browser Cleanup Tool.
The obvious method of testing this is to go into the AVAST program features and, assuming it is enabled, disable Browser Cleanup and see if that temporary file disappears.
It would be ironic if it is that which is creating this temporary browser info file backup. The tool is actually compromising the browser user's privacy. Presumably it is meant to be deleted at some point (Shutdown?) but if the file is being created on bootup or when a particular browser is being used it is effectively not temporary.