Page URL incorrectly states username is when it contains a period/invalid character

[taivlam]

LinkStack version

4.8.0

Description

When selecting a username on the Sign Up page, the text field for Page URL will erroneously report that a username is taken when it actually contains an invalid character (such as period/.) on the main LinkStack instance.

Details about your system

Linux/Manjaro Unstable with Brave Browser version 1.66.115-1 on the main LinkStack instance linksta.cc.

How to reproduce

Suppose multipartusername is the desired base form of the username and is not taken.

Using a pure alphanumeric multipartusername, hyphen separators like multi-part-username, or underscore separators like multi_part_username is valid.

However, multipart.username is invalid, since periods are not allowed. However, the form reports with client-side form message that says:

That username is already taken

Possible Solution

During the sign up process, if an invalid character is used for a username, then the form should tell the user that an invalid character has been used; and also the user should be told what characters are valid in usernames.

Additional Context

No response

[JulianPrieber]

With our current system this is the expected behaviour