Smash-ter
This is a very rare bug that many players may or may not experience, but there's a high likelihood that if two players have each other blocked in some worlds it can lead to the instance desyncing. Two examples are:
  • Game worlds that require player data to be synced, if two players in that world are blocked it could cause issues where the game world is unable to find the target players on either users' clients. Important for AI player targeting systems
  • Video players not playing videos properly, resulting in videos skipping a couple of seconds in random intervals or the video not playing for one of the blocked players at all until another URL is put into the video player's address bar.
I'm inclined to believe it could possibly be a networking issue between individual clients and Udon Syncing where there could be a lack of any compensation for when 2 players in an instance have each other blocked, but this is based on my layman's understanding of networking and the Udon system.
There may be more examples that I might have missed, one of these concerns would be from this canny post back in 2022 that is becoming a bit more prevalent in recent updates here: https://feedback.vrchat.com/bug-reports/p/blocked-players-can-sometime-still-see-the-user-that-blocked-them
Users are also welcome to share more examples about their blocking issues in this feedback post and hopefully VRC will take that feedback so it can be properly addressed.