How can you see if captcha character X is uppercase or lowercase, because sometimes I can't figure it out.
It doesn't matter.
Recaptcha is not case sensitive anyway.
I've never bothered with case and it is confirmed in this response from Recaptcha support here.
That response is a few years old though. Trying the online demo and typing in willfully the wrong case
this still showed up as "correct" after hitting "submit".