I will try to explain the problem briefly.
1.13 is beautiful and I have to recognize it but it also has many problems.
what has literally killed my world is as follows:

every time you leave the END (either by death or by victory) the normal world becomes truly unplayable, as pressure pads, levers and other things of this kind will no longer be activated, the boxes can no longer be opened. I tried to go into the nether to see if things were fixed but I found that the portal did not work anymore. the game starts to go jerky. when you destroy the blocks they are not dropped on the ground but simply the block "disappears". even the commands for example: / gamemode and all the others no longer work.
the most serious thing that killed my world is that after death and the discovery that the normal world no longer works, you are almost forced out of the world, the only problem is that the player's last position is not saved and therefore every time I enter my world I still find myself in the END, dead. every single time I press on reborn I find myself in the normal world with the same problems listed above.

My world has died for this, at least until you release a fixed version. I hope soon

among other things, I've noticed that farms are no longer working for some reason. the spawn of the monsters in the dark areas is strangely low.