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Autohide scrollbars solution for Firefox 57+ WebExtensions obstacles. Tips for tweaks are appreciated :) source: https://www.reddit.com/r/firefox/comments/6v6otw/webex_replacement_for_hidescrollbars/
< Feedback on Firefox 57+ autohide scrollbars
Only problem is, in Youtube, when watching a video fullscreen, a blank bar is shown below.
Great! Thx!