Instant death on opening the world, inventory items sprayed at the wrong place spawn

The bug

Instant death on opening the world, no obvious cause, inventory sprayed at the wrong place

Steps to reproduce

• Create world & get stuff (I used an old type world (my survival world), might be related, I tried a few times in an infinite world, but without success)

• Jump and while on the way down "save and exit", it takes some practice, but it could get it to work twice in a row, without changing anything else

• Go back into the world, death screen should be shown immediately

• extra weirdness: items can be sprayed either at spawn or at death position

It can be quite difficult to reproduce the issue, it doesn't appear to be very common or consistent. Just please don't treat it like some 12yr old zombie death salt.

<rant>

extra bug: couldn't find version, f3 doesn't work (Kappa of course, but for real, I just had to assume the release to be the "1.13 "equivalent"" and the inofficial wiki didn't help me either, also the beta was just "experimantal enabled" (28.12.2018))

All this terrible design for debugging trickles down into these even worse tickets, please talk to Mojang about this, how hard could it be to not hide everything away.

</rant>