Registration Date Changer - Product specifications

Change any member's registration ("Joined") date and time right in the Admin CP user editor, or set it
to the date of their first post in one click. Ideal after a forum import.

- Editable "Joined" date and time in Admin CP → Users → Edit.
- Entered in your own time zone, to the second.
- "Use the date of their first post" shortcut, showing that date.
- Validation: no invalid or future dates, with errors shown on the user form.
- Saved with the rest of the user form (one save, one set of errors).
- Untouched fields change nothing; new members still get today's date.
- Uses the existing "Edit users" admin permission; no setup.
- Built for XenForo 2.3.13 on its own user editor.

**Requirements:** XenForo 2.3.13+, PHP 7.4+.