[1.3.3306 - Base+Roy - Manjaro KDE] Mouse movement doesn't register if it's slow

[Hexicube]

RE: https://ludeon.com/forums/index.php?topic=55930

Not fully fixed on unstable branch, draggable things (sliders, scrollbars) still show the issue. The game also still lags when dragging, which is an issue when trying to drag-scroll, and that lag is more pronounced when there are more UI elements.

Side note: Would appreciate it if the topic isn't locked until the bug submitter verifies the fix, since I now have to make this separate topic.

[Hexicube]

Also still happens with some mod UIs, notably RimHUD. I've let them know via steam discussions.