MC-260857 has been fixed, but another similar bug is still there.
Display entities that are summoned with custom transformation will interpolate from the default transformation instead once the next transformation with interpolation is applied.
To Reproduce
/execute positioned ^ ^ ^4 summon block_display run data merge entity @s {block_state:{Name:"stone"},transformation:{scale:[3.0,3.0,3.0]}}/data merge entity @e[type=minecraft:block_display,limit=1] {transformation:{scale:[10.0,10.0,10.0]},start_interpolation:0,interpolation_duration:1000}Notice there's a chance that the display entity resets to the default transformation before performing the new transformation interpolation
Linked issues
relates to 1
Comments 3
FYI interpolation can be specified in the first command and it will still repro. The issue is unrelated to not setting those values.
Relates to MC-260897. Not sure if it is the cause of this issue.
Occasionally I can repro but a few rare times it works properly, but depends on where I spawn the block display. I believe the issue you're describing manifests occasionally when desync occurs and may be the equivalent of MC-260874. I believe there's some desync occurring between when the summon happens and when the data merge happens in the first command. Possibly doing your repro after triggering desync or running it on 20hz may make it visible. May be alright to keep this bug separate for now as this is a very simple repro.