steps to reproduce:
summon marker with some custom data
teleport the marker into another dimension
change the custom data of the marker
proceed to another tick
print the marker data
i've made the reproduction easier by making a datapack
steps to reproduce with my datapack:
go into overworld
run /function test:markertest
click on "Teleport to the nether" text in chat and press enter
click on "Print marker data" text in chat and press enter
what happens:
after the data is modified, it will stay modified only until the end of the tick... after the tick passes, it has previous data values
what should happen:
the data saves properly
notes:
this also happens when the other dimension's chunks are forceloaded
Can confirm:
[media]