MediaWiki:Katapulta.js
From Katapulta
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function AppendCategoryTreeToSidebar() { try { var node = document.getElementById( "p-tb" ) .getElementsByTagName('div')[0] .getElementsByTagName('ul')[0]; var aNode = document.createElement( 'a' ); var liNode = document.createElement( 'li' ); aNode.appendChild( document.createTextNode( 'CategoryTree' ) ); aNode.setAttribute( 'href' , 'http://en.wikipedia.org/wiki/Special:CategoryTree' ); liNode.appendChild( aNode ); liNode.className = 'plainlinks'; node.appendChild( liNode ); } catch(e) { // lets just ignore what's happened return; } } addOnloadHook( AppendCategoryTreeToSidebar );