How to reproduce:
1. Open the user attached project (TestMouseInput.zip) and make sure the "TestMouseInputCamera" scene is open
2. Enter Playmode
3. Hold down the left mouse button and move the cursor in a circle around the cubes in the scene
4. Press the space key and observe the movement and change in the graphs

Expected result: There is no change in the mouse movements or the graph behavior
Actual result: The movement becomes slower or choppy as if mouse input is registered at a lower framerate than the game is running in with the graph showing gaps between actual mouse inputs

Reprocucible with: 2019.4.30f1, 2020.3.18f1, 2021.1.22f1, 2021.2.0b12, 2022.1.0a7

Notes:
1. Reproducible on Ubuntu 20.04
2. Not reproducible on Windows 10
3. Issue isn't present in builds, only on the Editor