Sins Kriat 5 the Polygonal selection tool does not work with Group, Hidden or Locked layers, you can start the selection but when completing it it the selection disappears, using it with a unlocked and visible paint layer works just fine. The other selection tools has no problems and it’s only the polygon tool that has issue.
It’s not a pressing problem, more an annoyance then anything, the workaround is just making sure I’ve got a unlocked and visible paint layer selected when using the polygon selection (or just use the freehand selection), but I’ve lost count of how many times I’ve forgot.
Now the Alt + click Layer Text toggle for Isolate Active Layer does not seem to work.
Reset hotkeys and canvas imputes, reinstalled 5.0.5 the toggle works there, reinstalled Build #1701 and it doesn’t.
I feel like I’m compiling and I really hate that as I truly love Krita.
If something doesn’t work as expected and is reproducible please complain, no need to worry or apologize. Even better if you can report it as a bug on bugs.kde.org
The Apr 27 nightly Windows build also has this problem.
There is a keyboard shortcut for Isolate Active Layer, and it works, but it’s None by default so it may be some hard-coded thing for Alt+click.
Please make a formal bug report and post a link to it here.