When a user tries to delete their own account via the frontend profile page (/participant/username/?wpfaction=user_delete&_wpfnonce=XXX), it always fails on the first attempt with:

"User delete error: missing argument."

The server returns a 302 redirect to the members page, but the error is set. Clicking delete a second time works and the account is removed.

We confirmed via browser DevTools that the error is rendered server-side in the HTML. We tested flushing permalinks, deactivating all other plugins, and different user accounts — the issue persists. Custom URL slugs are configured (member → participant, members → participants).

It seems like wpForo does not correctly resolve the user ID from the profile URL on the first delete request. Could this be related to custom slug configuration or a PHP 8.3 compatibility issue?

Any help appreciated. Happy to provide more details.

wpForo 2.4.17 | WordPress 6.9.4 | PHP 8.3