In the games Minecraft from version 1.12 (with mods) and with the game Rising World, which is also based on Java, I have jerky movements for no apparent reason. And in the middle of the game (not at the start).
I consciously made sure that I was in a chunk when the error occurred. No. No new chunks are loaded. Bring nothing. Reducing the number of chunks loaded doesn't help either.
Is the mouse acceleration still active?
No she is not. The DPI is also in the lowest setting. It doesn't matter what speed.