The main page previously showed the name of the page as the heading. For example on https://nl.wiktionary.org/wiki/WikiWoordenboek:Hoofdpagina the heading of the page is "WikiWoordenboek:Hoofdpagina". This was problematic as the namespace is not always user friendly to newcomers.
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Another common use case was hiding the main page heading via CSS inside MediaWiki:Common/Vector.css, however this also hid the heading on diff pages. e.g.
Expected:
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Actual:
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A new change (T296969) allows more control/creativity over the text of the heading.
It is currently being used on Basque Wikipedia and MediaWiki.org
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This change can also be used to hide the heading. To do this you can [[ https://it.wikipedia.org/w/index.php?title=MediaWiki:Mainpage-title-loggedin&oldid=124897087 | blank the heading message ]] and remove any CSS in MediaWiki:Common.css or Vector.css that was previously hiding it ([[ https://it.wikipedia.org/w/index.php?title=MediaWiki%3AVector.css&type=revision&diff=124911925&oldid=121630135 | example on Italian Wikipedia ]] ).
This is documented on https://meta.wikimedia.org/wiki/Small_wiki_toolkits/Starter_kit/Main_page_customization#Hide/change_the_text_of_the_header