Interesting! I think I’ve struck this (but ended up just typing in the number): Beware When Pasting Phone Numbers Copied from Contacts - TidBITS:
Contacts on the Mac encloses all phone numbers in two zero-width (and thus invisible) Unicode characters
Odd-Egil “Oddzthrash” Auran I wish every phone number field would strip all non-number characters. Constantly running into problems with this. (And my mind fail to remember complete phone numbers anymore).
Leon Mika @odd I wish every number field, regardless of what it is, would do this. There's a service call B-Pay here which can be used to pay bills (electric, water, etc.). In order to use it, you need to enter in something like 12-16 digit number (it's like an account number). Usually on the bill they group digits with spaces but I can't include these spaces when I'm entering the number into my bank's website. Would be so nice if I could.
Miraz Jordan @odd I can't bear it when web forms insist I enter the number in a particular format — that's what software's for!
Dan J No kidding! “Don’t enter spaces between the digits in your credit card number”
How about instead I enter the one line of JavaScript you would need to make this not be my problem? 🙃
Scott Little @danj This is almost always someone who does not understand software dictating how a site should work. It makes me crazy though.