Affects Version/s: 1.16.21
Fix Version/s: None
If you throw ender pearls at the bedrock ceiling in the nether you can clip through and into the nether cieling. However once there you cannot build because the height limit is reached.
When i did this i had exactly 3 pearls and it took me 3 attempts to clip through, Once there i was stuck. I could not die. my hearts would never kill me from hunger. i could not build a tower to jump off. there was no hazards that would cause me to die.
In this case i was able to switch to creative and break down. however, if this was done a realm it would be possible for you to be stuck there forever without permissions available to change settings.
i did this again with a stack of ender pearls to see if i could get back down. the way the pearls are thrown it seems impossible/unlikely to clip back down through the bedrock ceiling. Even looking downwards and trying to lob a pearl gives the "Height limit reached" error text so you can only throw a pearl away from you and hope it clips you back down (which i could not get to happen with 5 stacks of pearls)
possible remedies for this kind of bug would be
- a hazard to kill yourself on like lava pools on the nether ceiling.
- allow building on the nether ceiling to make a tower to jump from.
- a nether-mite or bedrock-mite mob that spawns if the player is above 128 to kill the player when they are in an area they aren't supposed to be in.