#plugin

This is Ubuntu with libapache2-mod-php8.3.

@liam morland: What is the PHP integration with Apache Web Server on that platform? Is it mod_php, or FPM, or another?

As I already mentioned the problem occurs also on a production site on the same webserver after updating a clone staging site. Today I noticed that at first the production site wasn't affected after updating the staging site until I tried to clear the cache on the production site from the admin web interface and the error appeared again.

I just had this problem. It went away when I rebooted the server and ran drush clear-cache. A clear-cache by it self did not fix it. Running apachectl graceful and then clear-cache also did not fix it.