I am unable to search using any of the options on https://en.wikipedia.org/w/index.php?title=Special:Search
This came to my attention when a user reported that they were unable to search English Wikipedia's help files. It turns out that none of the "advanced", "everything", "multimedia", or "content pages" search functions are working.
All searches return the error "An error has occurred while searching: The search backend returned an error:"
Pine