smf-mw-auth Error: Call to undefined method MediaWiki\User\User::idFromName()

[von Corax]

I'm running SMF 2.1.4 and MediaWiki 1.43.1, joined by @SleePy 's smf-mw-auth extension (I'm not sure what version.) A very few of my users are reporting an error when they try to jump from the Forum to the Wiki, with the following error message:

Code Select Expand

[aB4entYZWYENsxV9akrX8wAAARM] /wiki/ Error: Call to undefined method MediaWiki\User\User::idFromName()

Backtrace:

from /home/brassgog/public_html/wiki/extensions/ForumSsoProvider/ForumSsoProvider.php(236)
#0 /home/brassgog/public_html/wiki/includes/session/SessionManager.php(542): ForumSsoProvider->provideSessionInfo(MediaWiki\Request\WebRequest)
#1 /home/brassgog/public_html/wiki/includes/session/SessionManager.php(248): MediaWiki\Session\SessionManager->getSessionInfoForRequest(MediaWiki\Request\WebRequest)
#2 /home/brassgog/public_html/wiki/includes/Request/WebRequest.php(867): MediaWiki\Session\SessionManager->getSessionForRequest(MediaWiki\Request\WebRequest)
#3 /home/brassgog/public_html/wiki/includes/session/SessionManager.php(167): MediaWiki\Request\WebRequest->getSession()
#4 /home/brassgog/public_html/wiki/includes/Setup.php(492): MediaWiki\Session\SessionManager::getGlobalSession()
#5 /home/brassgog/public_html/wiki/includes/WebStart.php(85): require_once(string)
#6 /home/brassgog/public_html/wiki/index.php(50): require(string)
#7 {main}
I have been unable to replicate this error, and most of my users do not see it, but those who do see the same message no matter what browser they use (we've tested with Firefox, Chrome and Edge.) I've had them clear cache and cookies, to no avail, and I'm out of ideas.

Can anyone see or suggest anything that might help me to nail down this problem?

Thanks,
Darwin

[SleePy]

You can try to enable debug logging in MediaWiki and check the log file for where it is failing in the process.
https://github.com/SimpleMachines/smf-mw-auth/tree/3bc9ac458912f7a8805e71c551aa21eef73f0cd8?tab=readme-ov-file#extension-troubleshooting