Slower sensitivity

Most likely caused by LWJGL update; the way the mouse input is handled is different now, the range of acceleration slider should be still enough for you to get the value you had before 🙂

Georgii, changing mouse sensitivity is not the same as enabling or disabling mouse acceleration. I'm sure LWJGL has some sort of toggle for enabling and disabling it. Can this please be properly investigated? Thank you.

@Georgii Gavrichev I use a trackball for minecraft (because its fun aight-- logitech M570) And it looks like the acceleration is my problem. The sensitivy to acceleration is lower in 1.13 and 1.14.2, more than it was in 1.12 like you said likely because of the LWJGL update. Can you give me some more information on this update or its implementation, maybe about how to adjust acceleration, or maybe even add in an acceleration slider setting in the Controls part of Settings in minecraft? That would be a needed setting I think, especially in my situation and others. Thanks!

@Georgii Gavrichev i use a trackpad mouse sensitive up all the way and it's still super slow in 1.13 and 1.14 a fix would be nice 

UPDATE: 1.14.3 made the acceleration or sensitivity back to the way it was before 1.13. This fixed the problems I was having in my previous comment, and should fix the problems caused from this 1.12 to 1.13 update that changed acceleration or sensitivity

another update for 1.14.4: it gets messed up again in this update and is unlike the way it was before 1.13, but to fix this, go into

options > controls > mouse settings (top left of the controls window) > turn "raw input" to off. 

that made it go back to the way it was before 1.13.