Preparations for a patchset v3 for the Linux bridge regarding #multicast has progressed, have incorporated most feedback from the mailing list now. The feedback was actually a lot more "tame" and overseeable than I'm typically used to for my typical "early" v2 PRs with such a long list of commits :D.
And it feels so much nicer to work with and restructure such patches with having done extensive test scripts for/in the Linux selftest infrastructure early on :D.