Community Wishlist Survey 2022/Install CirrusSearch extension on all wikis

Proposed by GTrang

Proposal summary: The CirrusSearch extension should be installed on all Miraheze wikis, including the Meta wiki, by default.

Full proposal: Currently, there is only basic search functionality. It would be better to install the extension to get advanced search functionality so that one could use, e.g., the "linksto" and "incategory" keywords.