Can't upload images to wiki

Here's a screenshot:

Inspecting the request in the console shows this error:

Fatal error: Declaration of Wikimedia\ParamValidator\Util\UploadedFile::getStream() must be compatible with Psr\Http\Message\UploadedFileInterface::getStream(): Psr\Http\Message\StreamInterface in /var/www/html/includes/libs/ParamValidator/Util/UploadedFile.php on line 86

There are some hints on StackOverflow that make me think upgrading may be the best option here. I believe the problem is that some streaming bits of MediaWiki now expect there to be type hints and the upload-y parts do not offer them.

Related issue: https://git.coopcloud.tech/coop-cloud/organising/issues/641

Thank you! I think upgrading is the right thing to try; it shouldn't take long with abra, we can try this on the next meeting or after updating Mastodon?

Reproducing first in alpha.wiki.social.coop and updating that would be ideal.