Hi Peter,
I got this error on multiple websites, Joomla 4 and Joomla 5:
screenshot.webjongens.nl/qGuYeAzG
When I depublish Regularlabs, the error is gone.
The sent error is on a clean Joomla 5 installation, with few extensions active.
Another live website I used a backup to get the right version again.
Does this ring a bell? Do you like to have more information, if yes, what?