I used to have an excellent form filler that allowed multiple identities (different countries for shipping), but after FF Quantum it no longer works.

So I went on the hunt for a new one. The best I can come up with is one that seems to think we are all programmers and of course we know what the fields/selectors are called.

This is the filler I'm using (which only allows one ID unfortunately)
https://mybrowseraddon.com/autofill-forms.html

About a third the way down it says:
If you are not familiar with CSS Selectors, please visit this link in w3schools website to get more info

but that is also useless at telling me what the selector names can be (it lists.....one name).

So does anyone know where one might find a list of commonly use selector names please?
I've put these in, hoping they might be right:
Capture.JPG