I tried fist on firefox, then now on chrome. The same.
Two things I think :
first, the computer and the browser are set for a region, for me France, and you USA (I think). So no issue for you with dot, and for me yes.
Second, when I enter a letter instead of a number, I do’nt have any red validation field, which would be the interest of having a “number “filed when I write a letter.
Then, a dot, in france, is considered as a texte caracter. Not a comma which is a regular number caracter.
So when I enter a lettre or a dot, intead of red alert which couldn’t let me following the form, it’s validated and regsiter a 0 instead of this letter or dot. This mean thaht the field is recognized as number filed and refuses letters. But the form let is pass.
I know I could use a pattern in the advance stting. That why I asked. But trying to understand how to write the pattern “accept only numbers and comma, withou limit of number”, I couldn’t succeed…