Firefox extension to hide whatsapp contact number of customers -- 3

Must be done as Firefox add-on and must sync with google contacts I need to hide the WhatsApp contact number of conversations on WhatsApp web and replace the contact number with a contact name. I need to hide and replace on every place when the contact number may appear 1. Chat list 2. Chat header 3. Contact info If the contact it's already saved, just replace the number in all the places where the contact number may appear with the name saved. If the contact number it's not saved, generate a unique name and store it in google contacts, also replace the number in all the places where the contact number may appear with the name saved. I need the number to be replaced quickly (cant take more than 1 sec to be done) because someone can steal the contact number. Habilitada