Seaching on UserBase
Searching on UserBase is broken. The standard wiki search tool are of limited use: The regular search finds strings on all translated pages as well as on the English pages; and it can only search for strings, that are displayed to readers. The WhatLinksHere tool only finds a fraction of the pages linking to a particular page.
We had a solution using the DPL extension (the 3. party version). That extension is no longer developed and is incompatible with recent version of mediawiki. There is another extension, DynamicPageList3, which is installed and should be a drop-in replacement for DPL. However the new extension doesn't work for searching: there is a bug in the 'includematch' parameter.