When one is new to MediaWiki development, one is likely to look at Special:Version early on, as often instructed by documentation.

During an introductory session last week, I noticed that referring to the "Installed extensions" section there was a brief moment of confusion as this section doesn't exist unless there are also non-zero extensions installed.

This special page is not an encyclopedic article or end-user interface, where an empty section may be unhelpful. Rather, it's meta information, and the fact that no extensions are installed is useful information to state.

Outcome

• Ensure the " Installed extensions" is always present.
• When no extensions are installed, output a sentence that says so. As all sentences in our software, this should be a localized sentence.

This task will cover:

• SpecialVersion.php
• SpecialPage interface: Which methods are invoked by the request handler? Where does execution begin?
• OutputPage interface: How does text end up on the page?
• Html.php utility: How is HTML formatted?
• Localisation system:
  • Defining a new message, documenting a new message, accessing and outputting a new message.
  • https://www.mediawiki.org/wiki/Localisation