Analysis Top: Add option to filter nominal branches and read generator metadata again

Title says it all, this is a manual sweep from 21.2 into master. It includes two kind-of unrelated things (sorry about that) since it makes some conflicts resolution easier from our side.

The MR that is swept is !41538 (merged) And the related metada part was originally removed in !38919 (merged) and is brought back since this metadata works again.