login: When requireEmailFormatUsernames, check client-side that username looks like an email address

[chrisbobbe]

It's nice to avoid a round-trip to the server when we can tell the user what's wrong and how to fix it.

[davidodejobi]

Hi @chrisbobbe,

I've been digging into the codebase and still getting familiar with it. Could you assign this task to me, so I can start diving in and contributing?

After reviewing the issue and looking at the codebase, I'm planning to implement an additional validation if the requireEmailFormatUsernames is true. This will involve adding localization for a message prompting users to input a valid email if the format is incorrect.

[chrisbobbe]

Hi @davidodejobi, welcome! Could you describe the validation you have in mind? Please explain what a valid email address is and how you would like to check if the input is one.