+x+xThat's strange. Is it present at all in the alt-tab list? Did you try any keyboard shortcuts to perhaps move it onscreen?
No - I'm just going through a few permutations to recreate the scenario. Alt tab would very briefly show the main Skydemon window and 'I'm still here' overlay, but then the document browser would appear over the top of it, and locked with no way to get back to the overlay.
It's on vanilla Windows 10 (not Mac wrapper) - the only non-standard aspect is 4k display scaling - but I don't think that's the cause.
I think I can recreate this consistently (well, twice!)
Login to Skydemon, open Document browser, maximised.
Toggle to other programmes, and stay away for long enough.
When I ALT-TAB back to Skydemon both the Document Browser and Skydemon appear as separate options in the ALT-TAB mosaic.
If I select Skydemon - that's fine, 'I'm still here' is accessible, and I can carry on.
If however I select Document Browser - it's just a frozen document browser window, no 'I'm still here' box. Subsequent attempts to then ALT-TAB to the main Skydemon window don't work - just returning me back to the frozen Document Browser window.
The slightly bizarre bit, is if I then open any other random programme (e.g. explorer, or command prompt) and then close the other random programme - the 'I'm still here' box then reappears.