It appears that Facebook is testing a "Downvote" button which allows users to mark questionable comments as misleading, offensive, or off-topic. However, it is only intended for comment moderation.
This Week in Rocket Launches #116
China to send people to space and SpaceX to resupply ISS
Windows 11 Beta Channel fixes issues with SMB, memory leak, NTFS, LSASS
windows 11 insider preview