MediaWiki has many extension systems. There is a way to add javascript code or CSS upon page load, and to configure for this to happen independently for each user or site-wide. See [https://www.mediawiki.org/wiki/Extension:Gadgets MediaWiki's documentation].
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MediaWiki has many extension systems. There is a way to add javascript code or CSS upon page load, and to configure for this to happen independently for each user or site-wide. See MediaWiki's documentation [https://www.mediawiki.org/wiki/Extension:Gadgets here] and [https://www.mediawiki.org/wiki/Manual:Interface/JavaScript here].
* common.js is site-wide javascript, called during any page load and defined on PersonalData.IO at [[MediaWiki:Common.js]]
* common.js is site-wide javascript, called during any page load and defined on PersonalData.IO at [[MediaWiki:Common.js]]