10 Things You Did Not Know MediaWiki Can Do

MediaWiki is deeper than it looks from the default interface. These ten capabilities are all real, documented and often overlooked — a mix of magic words, configuration and built-in features that solve common problems without extra extensions.

1. Hidden categories — put __HIDDENCAT__ on a category page and the category stops appearing in the footer of member articles while remaining searchable and admin-visible. The classic use: quality-control categories like 'Pages needing cleanup'
2. Collapsible content — wrapping anything in <div class="mw-collapsible"> makes it expandable/collapsible on the reader's click, no extension needed. Liven up long lists and step-by-step instructions
3. Temporary accounts for anonymous editors — with temporary accounts (available since MediaWiki 1.40, and standard on Wikimedia since 2024), IPs no longer appear in public history; config via $wgAutoCreateTempUser
4. Copy-upload by URL — $wgEnableUploads + $wgAllowCopyUploads lets users import files from a remote URL instead of downloading and re-uploading; admins can restrict domains wiki-side on MediaWiki:Copyupload-allowed-domains
5. The {{=}} magic word — templates that need a literal equals sign in a parameter value use {{=}} (renders as '='), avoiding parser breakage
6. Group-specific CSS — MediaWiki:Group-user.css, MediaWiki:Group-sysop.css etc. load per user group: show a feature only to logged-in users without JavaScript
7. Lua scripting via Scribunto — the Scribunto extension (bundled) runs Lua inside templates: loops, tables and string handling that wikitext simply cannot do, powering most of Wikipedia's complex templates
8. Visual diffs — on wikis with VisualEditor, the diff page offers a toggle between wikitext and a rendered side-by-side visual diff; reviewers of prose-heavy edits prefer it
9. #ifexist for conditional content — {{#ifexist:Page|A|B}} (from the bundled ParserFunctions) renders different content based on whether a page exists — used for "create this article" links and dynamic navigation
10. API-driven automation — everything (create, edit, delete, search, import) is reachable through the Action API; with the edit right, bots and scripts automate bulk imports, reports and sync — the foundation of every serious MediaWiki workflow

Most of these cost nothing to enable and cover the quirky middle ground between 'default wiki' and 'extension zoo'. The documentation links above are the authoritative reference for each feature.