Unused categories

These categories are currently empty. Empty categories are often candidates for deletion, however this is not always the case. In particular, there are some categories designed to flag up pages that need attention (e.g. Category:Cleanup) which will be empty if no problems of that type exist. If most cases these categories are marked with the {{EmptyCatGood }} template, but if in any doubt err on the side of caution.

Showing below up to 6 results in range #1 to #6.

1. $wgSMTP/ar
2. Archived Semantic MediaWiki extensions/en
3. Archived Wikibase extensions/en
4. Extensions using hooks from redlinked sources/en
5. Extensions using redlinked hooks/en
6. Extensions using unrecognized hooks/en