Just add:
#root ~ div { display: none !important; }
.. to your custom stylesheet for medium.com (and all their crappy subdomains and clones) to get rid of that super irritating social media popup thing.
Either that or use Firefox's underrated "reader view" by pressing F9. It's totally worth it.
Stylus for Firefox: https://addons.mozilla.org/en-US/firefox/addon/styl-us/ Stylus for Chrome: https://chrome.google.com/webstore/detail/stylus/clngdbkpkpe...