James Usher

Maybe items that are thrown on the ground (entities) could stack higher than 64 and are stacked back to 64 when they go into a player's inventory. And the amount added to the player's inventory is simply deducted from the pile of thrown items and when you /give it gives just summons the items as an entity with a tag that sets the number of items it accounts for. E.G: Thrown items could stack to something like 32767 meaning that 100000 tnt could be 4 entities instead of about 1500? Not sure if Mojang will fix this though, as you can just not give yourself thousands of items although this would fix any lag caused by thrown unstackables also, as thrown unstackables could also stack to something like 32767.

Did you edit the .dat file, I think the seed is stored there?

Please provide more information, also this sounds like it should reported on the technical bug reports.

I also hope this intentional it is incredibly useful.

They are entities, you can view the outline with hitboxes.

So they despawned... Or are they not meant to despawn? If they are not meant to despawn, maybe they just walked away?

Try changing to another difficulty then changing back to easy, if that doesn't work it MAY be intended in newer releases.

Can confirm in 21w03a

Please clarify if this is a bug in the game or a typo in slicedlime's code.

Just had the same problem in my survival wold, can confirm feeding kittens will make them stand up in 21w03a

 This is intended, you can only use 'raw' fish.

Can confirm.

This is a launcher bug, there is another page of launcher bugs (I think)

Please provide the crash report, instructions on how to find  the crash report here Tutorials/How to get a crash report – Official Minecraft Wiki (gamepedia.com)

NameMC is not always correct. It also could have been blocked by mojang

Did you make changes to your .minecraft folder or install a mod loader/hacked client that would make any changes to your .minecraft folder? It was less likely to be installing a mod loader/hacked client but may still be possible. Using the information provided can't really help apart from that. Adding more information would be greatly helpful to fixing your bug report. Also if you changed computers you will no longer have the worlds on your new computer but you can transfer the worlds manually. I would also recommend making backups of your world by copying the world folder to your desktop. If you did you make changes to your .minecraft folder or install a mod loader/hacked client or change computers then this is not a bug.

As said above adding more information would be greatly helpful to fixing your bug report.

JamesNotBetter

This has been the case for quite a while, I always thought it was intended because the water is slightly lower than full blocks (I think.) If water is a full block then this is most definitely a bug, but if the water is lower than a full block it MAY be intended.

You are playing Bedrock Edition. This is the bug report page for Java Edition. (Please correct me if I'm wrong)

You can delete the chunks if you wish using Releases · Querz/mcaselector · GitHub THIS IS NOT A FIX FOR THE BUG but it will let you delete the affected chunks and then they will be regenerated without the command blocks which will allow you to go in the affected chunks until a fix is released (requires java.) more info on deleting chunks here Tutorials/Updating old terrain – Official Minecraft Wiki (gamepedia.com) this java app is not made my Mojang.

Sorry about that, looked for duplicates but could only find spectral arrow bugs.