You should abandon ABP 2.9.1 and EHH (wont work anymore since FF 57 landing in november).
Install ABP beta:https://addons.mozilla.org/firefox/addo ... sions/beta
and use the "block element" feature (clicking ABP icon, "block element") to replace (not so strong ...) EHH.
I tried downloading the beta version (Version 188.8.131.527 beta) and the 'Block Element" option is there. Before Firefox updated to Quantum I was able to use it fine, but now when I click it the popup box is blank. I tried just pasting the URL of what I wanted to block but when I hit "ADD" it does nothing. I mean, the popup doesn't go away or anything thing, it just sits there blocking my view and not adding the element I want to block.