Thanks for the pointer Luka That’s a cool program. There is a wider thread covering Text input validation here How to Test a Text Field
I’m not validating or trying to break any applications, merely verifying the user experience on Mac/Windows/Linux when using their bog standard keyboards, which are all different. So I’m testing E2E, not just the middle bit here, the Naughty string list completely bypasses testing the key-up key-down and multiple-keys-at-once-depressed side of it all actually even works. Which I should have stated, is my actual test case here 