Note: After saving, you have to bypass your browser's cache to see the changes. Google Chrome, Firefox, Microsoft Edge and Safari: Hold down the ⇧ Shift key and click the Reload toolbar button. For details and instructions about other browsers, see Wikipedia:Bypass your cache.
// addPurge
addOnloadHook( function (){
    var x = document.getElementById('ca-history');
    if(!x) return;
    if(x.children) x = x.children[0].href;
    else x = x.childNodes[0].href;
    addLink("p-cactions", x.replace(/=history/, "=purge"), 'purge', 'ca-purge', 'Purge the internal cache for this page', 0);
});


//