Creative flying touch ground false simulation

[commandblock2]

Describe the false positive and how to replicate it

creative-flight-flag.mp4

To reproduce simply double press space to fly, and then press shift until touch down.

Since all the flag values are different, I reproduced some (not the ones in video) and pasted four of them.

There has been a update in movement in 26.2 on how velocity is set(now in the function responsible for bouncing the player), which maybe unrelated to this specific one, but I am not exactly sure Entity.movement.

Grim Log

https://paste.grim.ac/HucPSr3GvX; https://paste.grim.ac/WrQas8jI0E; https://paste.grim.ac/r9vpDVOm7B; https://paste.grim.ac/fEriUB77Dv

Grim version

Grim Version: 2.3.74-2614909

Server version

Paper version 26.2-47-main@ad5d26a

Client version

Vanilla 26.2 (Launched from PrismLauncher, absolutly no mod)

Plugins/Mods

> plugins
[17:22:40 INFO]: ℹ Server Plugins (1):
[17:22:40 INFO]: Bukkit Plugins:
[17:22:40 INFO]:  - GrimAC