On two servers running Debian 10, Apache 2.4 (Debian 10 deb), PHP 7.3 (Debian 10 deb) , PostgreSQL (Debian 10 deb), I’ve tons of these errors:
Error PHP Method OC\L10N\L10NString::__toString() must return a string value at /var/www/html/lib/private/L10N/L10N.php#109
2020-04-02T19:13:05+0200
Error PHP vsprintf(): Too few arguments at /var/www/html/lib/private/L10N/L10NString.php#79
Are they all reporting the same problem? The message night be related to a problem with the translation file. That’s the reason why I asked you to switch to a different. language. Can you narrow down the problem to a specific page request or activity?
I see these error messages in PHP only from the admin console, when I view the logging section.
No user reports problems, only the log console.
I can’t set a different default language, there are more than 350 users per single server.
The interesting thing is that this error appears in the console repeatedly every 30 seconds.
I use a cron job to perform background operations set every 5 minutes.