I just used softaculous to upgrade our Mediawiki installation from 1.23.6 to 1.26.2 on a Litespeed server. The script appeared to installed the latest SyntaxHighlight_GeSHi extension, and I also see a recent composer.json in the folder. But I am seeing Category:Pages_with_syntax_highlighting_errors on every wiki page that uses the extension.
I looked at the extension page and noticed the recommendation to use
wfLoadExtension( 'SyntaxHighlight_GeSHi' );
so I put that into my LocalSettings.php instead of the old "require_once..."
but that doesn't change the error indication. I don't know what else to try - suggestions are welcome.