If UI scaling is set to a value other then 100 then the unit tab will be shortened. You can actually see this effect from the menu when changing the HUD scale value. The amount of units shown, as well as how squished their portraits are, seems to be a bit random. Perhaps the scale script is referencing another script it's not supposed to?
Sometimes scaling will remove the scroll arrows, or leave out units on the list. I can't figure out how to reproduce either of those but I suspect that the missing units on the list may be units I had created after setting the UI scale when I first realized something was wrong.
Overall whatever sizes and redraws the units tab for HUD scaling is doing multiple screwy things, vs when scaling is at 100 and the unit tab seems to work perfectly for me.
I noticed this in My Pet Dungeon, I don't have a save handy outside My Pet Dungeon to test. I'm on a 1920x1080 fullscreen, tested in windowed 1024x600. Email me if you need more info.
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