Is there a way to set it up so user@example.com can be a lemmy account and also a mastadon account? I seen people using subdomains like user@lemmy.example.com and user@mastadon.example.com is this nessasary? Could u also set up a matrix account with the same user@example.com? If not what woukd be requured to change to make this possible?
So u cant just do some weird routing rules and make it work.