NTHNer but here is the one I use. It's old but it still works a treat: https://alisdair.mcdiarmid.org/kill-sticky-headers/

    (function () { 
      var i, elements = document.querySelectorAll('body *');

      for (i = 0; i < elements.length; i++) {
        if (getComputedStyle(elements[i]).position === 'fixed') {
          elements[i].parentNode.removeChild(elements[i]);
        }
      }
    })();