Sat May 23, 2015
ssError message: preg_match(): Compilation failed: group name must start with a non-digit at offset 8 in includes/MagicWord.php online 902
Reference: http://www.mediawiki.org/wiki/Manual:Errors_and_symptoms All pages have no content, but when editing a page the wiki text is there Optionally with those error messages:
PHP Warning: preg_replace(): Compilation failed: group name must start with a
non-digit at offset 4 in /var/www/wiki/htdocs/includes/MagicWord.php
This is caused by a change in PCRE 8.34. You need to downgrade PCRE, or update MediaWiki to version 1.22.1 or newer (see task T60640).
There's a patch in https://phabricator.wikimedia.org/T60640 I'll try to apply it tomorrow.
Probably Hetzner decided to upgrade a library on our server.