This is an updated version of Alisdair McDiarmid's most excellent Kill Sticky Headers.
It's a bookmarklet (a javascript function you can add to your bookmarks bar) that removes sticky elements in a webpage.
Add a new bookmark, and use the code below as the URL.
(javascript:void function(){(function(){var e,o=document.querySelectorAll("body *");for(e=0;e<o.length;e++){var t=getComputedStyle(o[e]).position;("fixed"===t||"sticky"===t)%26%26o[e].parentNode.removeChild(o[e])}})()}();
(function () {
var i, elements = document.querySelectorAll('body *');
for (i = 0; i < elements.length; i++) {
var pos = getComputedStyle(elements[i]).position;
if (pos === 'fixed' || pos === 'sticky') {
elements[i].parentNode.removeChild(elements[i]);
}
}
})();