Mouse cursor lag in editor

Basically, when I move the mouse cursor when the editor window is focused, I get really bad cursor lag, but only when the cursor isn’t performing an action - when I drag an object, editor camera, etc., it’s smooth like normal.

It’s not the project. I’ve tried 3 different projects: my current project, a fresh project in the same editor version, and an older project in a different editor version. All have the exact same level of cursor lag. I have also uninstalled all my editors as well as Hub and reinstalled using a fresh Hub install (got a new installer from the website). I’ve also changed the install location for the editors. No change.

I noticed this issue today, after a day of not using Unity. My last Unity day it was perfectly fine, running normally with no lag or issues. I closed the editor and the next day all I did was enable hardware-accelerated GPU scheduling in Windows system settings (for Halo Infinite performance… it didn’t help). That was the only major setting I changed between when Unity ran fine and when the lag started. Disabling it again didn’t change anything. So now the environment of my PC outside Unity is exactly where it was before the issues started, but the issues remain. I have no idea what’s going on, unless there’s some global Unity user settings that are botched and affect all projects and don’t get removed with uninstalling.

Having the same issue with unity 2020.3.24. I can confirm it’s not any of my scripts as I tried it with the unity standard first-person asset and it still happens. I can move using WASD and the movement is very smooth but as soon as I move my mouse the lag begins.