Windows 10: Alt-codes not working on Notepad

Something very strange is happening with Notepad. This is a new problem appearing a few days ago. Typing 'Alt-26' works the first time, then a strange character appears the second time, then an empty box, and then nothing appears no matter what Alt-code I try. Sometimes it works if I spam 'Alt-26' rapidly as you can see in the video provided. This situation repeats when I open a new Notepad session as you can also see in the video provided. Today this doesn't happen in other applications, however, a few days ago it also happened in other applications so I don't think it's only a problem with N

:)

 

Little Alt Code Utility

It does do that, mlee. All buttons have tooltips with the alt code and a description listed in it.

The masculine ordinal number in Spanish, Italian and Portugese? I'm not even sure what it is for ... lol

 

Little Alt Code Utility

What's does it do that a list in notepad won't?

 

No Alt codes working

I've found that no alt codes appear to be working using either left or right alt keys. I tried a few things suggested by an answer to a similar question ( Redirecting
) which has made absolutely no difference.

Other than Alt codes the alt buttons both work normally, likewise with the numpad.