Consider Using Localized Input Masks for 'Phone' and Other Restricted Inputs (64% Aren't Taking Advantage of Input Masking) – Articles – Baymard Institute
New Firefox phone-masking feature keeps your number away from spammers | TechSpot
Phone number mask: CS-Cart add-on by Cart-Power
How to Use Number Masking: Examples and Use Cases
How To Mask Your Phone Number With Another Number | Burner | Burner