a leap in the dark… did you have a dedicated mouse driver of the maker of the mouse installed maybe driving the focus to the presumed control (here measurement box).
Oh, I just remembered something. Every now and then I get a major Nvidia graphics driver crash while using Sketchup. I wonder if I need to update my graphics card and maybe the graphics driver is causing some feature issues with sketchup?
I have had problems with W10 basically not recognising some hardware and simply installing the most basic driver it can (or not installing any driver at all). I would recommending actually going and finding the specific mouse driver.
I remember a lot of topics where the deinstallation of a specific mouse driver was the solution for a problem with SU, so I wouldn’t recommend this step.
I remember all those posts recommending using the default MS mouse driver, but never followed that advice. In order to fully use all the functionality of mice I get, the manufacturer driver is required.
Once I experience a very nasty mouse driver issue - which only affected SU performance. Installing a new driver fixed that problem.
using the latest nVidia driver version is obviously the first thing to do if affected by issues in this area… for evaluating if the video sub-system causes the issue, just disable “Window > Preferences > OpenGL > Use Hardware Acceleration”, if problem vanishes the driver causes the problem.
I have made it worked all the time. Just precisely follow the format for specifying the dimensions. If in doubt draw manually and see the dimsnsion box on the left bottom corner.