I would understand why you would not allow the plus (+) character because of the aliases feature *
but not why you would not allow the remaining !#$%&'*-/=?^_`{|}~ characters and why it has to start and end with an alphanumeric character.
but I can imagine that fixing this would require changing somewhere in the code base a regex pattern for parsing the alias (the part after the plus in the local-part of the email address), probably making it a little more complicated.
so I should have titled this post "allow us to have whatever spec compliant characters (excluding +) in the local-part of custom domain email addresses" , I can't edit it now.
Wis
I would understand why you would not allow the plus (+) character because of the aliases feature *
but not why you would not allow the remaining !#$%&'*-/=?^_`{|}~ characters and why it has to start and end with an alphanumeric character.
but I can imagine that fixing this would require changing somewhere in the code base a regex pattern for parsing the alias (the part after the plus in the local-part of the email address), probably making it a little more complicated.
so I should have titled this post "allow us to have whatever spec compliant characters (excluding +) in the local-part of custom domain email addresses" , I can't edit it now.
* https://protonmail.com/support/knowledge-base/creating-aliases/