If you're unfamiliar with SimpleLogin, heres the idea. Everytime some website asks for your email, you click the SimpleLogin extension, and it generates a new email alias. You click your Bitwarden extension and save your email and generate a passsword. You fill out the "create user" info by clicking ctrl-shift-L (autofill password for Bitwarden) and you're good! Emails sent to the alias go to your normal email inbox, but if you start getting spam to your alias, you can just kill that alias.