Carrying on from the sidebar spacing issue thread, I’m experiencing just this. In both the WIP and 5.3. I work for about 5 - 10 mins and then the behaviour becomes very laggy. It seems to be connected to switching back and forth between viewports - something I do a lot, using the tabs below. Just to be more specific, with an object selected.
This happens in both new and old files and doesn’t seem to be connected with the complexity or size of files - it happens even in a new file with just a few lines.