I found it bit confusing that the text is "Enter a valid username", when it will take anything even non-user names.
My preference would be to change the wording to "Enter your name". If a user gets a specific link in their email, we already know their username and if they are logged in, we have it too.
Also, make the enter key submit the name. Currently have to click on the arrow (Safari) or push the arrow (iOS Safari)
Also, make the enter key submit the name. Currently have to click on the arrow (Safari) or push the arrow (iOS Safari)
Already developed.
The placeholder is changed, the static text will stay as it is, to state clear, that there are conditions on the user name.



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Already developed.