This horrible behavior. I've been playing for years and didn't know this, and having a couple shulker boxes of stuff that took hours to create vanish without warning is a bug, esp. when there is no cause to clear the blocks...the platform had plenty of space to spawn players. The fact that this was opened 9 years ago means "Normal" priority is to ignore it.
I did a search, but that MC-902 didn't come up. It does look like a duplicate. Either way, it is a horrible "feature" and needs a different solution. Losing shulker boxes full of netherite equipment with no warning whatsoever is a rage quit scenario. Don't allow blocks to be placed on the platform instead or at least only clear blocks if the incoming player would actually have a problem. There was plenty of clear space to spawn.
As in the picture, it is only snowing over for example the tree with snow on it and any other square with a snow layer at this particular Y level, so there are gaps where there isn't snow covered ground. Seems to me it is at a particular Y level it should either rain or snow, not only snow where snow happens to be. I also found if the snow is removed, it still snows only over the coordinates that generated with a snow layer and placing snow does not start snowing at that spot. It just looks odd, but may be as designed...
Ditto. Converted pre1 world to pre2 and first thing I noticed was the ender chest was invisible.
Duplicate of https://bugs.mojang.com/browse/MC-166004
Duplicate of https://bugs.mojang.com/browse/MC-166004
Also have the issue. I backed up my world before entering the end, killed the dragon, then approached the end gateway. It was over land so I went directly below it and looked up. That's when the game crashed and automatically saved the game. Loading the saved game just crashed immediately. I restored my backup, killed the dragon again, and approached the end gateway again. I looked at it the whole time and it didn't crash until I was directly below the gateway and looking up. I added my crash report (crash-2019-11-24_18.54.14-client.txt).
I saw the same issue after updating a 19w44a world to 19w45a. Every few seconds bees in my nests exit briefly and disappear into the next again.
Is it intended that when I set a shulker box full of high tier items down and another player comes through and it vanishes? That's a bug. clear the space around the head of the incoming player if you must and regenerate the obsidian, but not the whole platform.