shouldCauseReequipAnimation not patched in to ItemInHandRenderer?

[Tslat]

It looks like the patch that put ClientHooks.shouldCauseReequipAnimation into ItemInHandRenderer#tick has been removed
I didn't check all versions, but in 1.21.1 it was there, and as of 21.4.65-beta, it's not patched in anymore, and as a result that method doesn't work/do anything

[XFactHD]

This is a known issue. The patch was dropped during the port to 1.21.4 as that introduced the vanilla flag on "client items" (similar idea but limited to switching between different items) which broke this feature in several ways.
Getting this to work again is on my agenda but the primary reason this hasn't happened yet is that just reintroducing an effectively equivalent patch doesn't actually make this work properly again. When the vanilla flag is set on a "client item", the held item will switch immediately but the hand movement will still play (see video from vanilla below where the paper item has the flag set). The Neo hook excibits the exact same (arguably broken) behaviour with a minimal fix.

Minecraft.2024.12.03.-.03.39.23.01.-.edit.mp4