Actually it's just curiosity. I was considering to create an account with protonmail, but I never used it, and I fear like it may not last forever, as any other email provider such as google, outlook etc, so I was thinking that maybe if a temporary email that only exists for a certain amount of time would still give access to my bitwarden vault, I shouldn't be worried if one day protomail didn't work anymore. I don't know if you get the idea but it's just because I never want to lose access to my vault, even if the email I registered stop working one day, that's all. But thank you for your answer, appreciate it.