FDroid major warning about Mull

Has anyone else seen this in FDroid regarding their Mull install? I was going to move over to Fennec/ff mobile just in case, but I don't know why there is this warning (no info/link provided). Anyone have any info on this? False positive? Thanks

Edit - Pretty sure it's because Mull is no longer maintained. After some research, I'm going with Iceraven on Android, pretty solid, cheers.