This is caused by the PHP 8.0 upgrade.
Displaying the diff throw an error:
Unexpected non-MediaWiki exception encountered, of type "Error"
[e8db1406] /plugins/mediawiki/wiki/project1/index.php?title=Main_Page&diff=21&oldid=20 Exception from line 436 of /usr/share/mediawiki-tuleap-123/includes/diff/DairikiDiff.php: Call to undefined function each()