Last modified: 2014-10-24 14:47:37 UTC
When 'validate' modifier (http://www.mediawiki.org/wiki/Widgets#Validate_modifier) is used on widget parameters, sites that use PHP version < 5.2.0 break because filter extension is not available: http://us.php.net/manual/en/filter.installation.php
Proper solution is to upgrade PHP, but code should be modified to display an error in place of a widget.
The oldest MediaWiki version currently supported is 1.19 and that requires PHP 5.2.3, hence closing this ticket as obsolete.
Waiting 5 years works pretty well - if nobody is crazy about it, means it doesn't need to be fixed ;)