The Firefox development team should make Firefox Relay a service like SimpleLogin. You should also turn LockWirse into something like Bitwarden, for example. A lot of people will be willing to pay for good services.
Firefox Relay lacks essential features and has many limitations.

Just 5 aliases at the max? Almost everyone has loads of accounts and/or newsletter subscriptions. The point of aliases is that with them you can easily find out the culprit whenever such an alias is being abused.

would be better without the badge thing in the username / email field it ruins my site in a way it cuts of half the field, it needs to be placed somewhere else either above or to the side but not instead of. for context see page using the addon https://jnet.sytes.net/login.php

Great app with room for improvement. Unfortunately one cannot auto-fill any of the aliases and has to log in every time to retrieve them. Furthermore, there is no way to generate more than five aliases, and Firefox does not allow automatic completion of login information, at least for me using Bitwarden (using two-factor authentication under these circumstances just adds to the lack of user-unfriendlyness).

I installed it, and tried to connect to a site I already had an account on. When I click on the email address field to of my login, I cannot type anything anymore. I see only the Firefox RElay icon, even my password vault icon disapeared. I have no other choice but using Firefox relay, so I cannot even enter the email address I signed in with to change the address to a generated alias. I had to go to preference to unclick the option "Show relay Icon in email fields on website". Not practical at all.