Does what it's supposed to do on Youtube, but not perfectly.
When you reload a page, the time appears for a second (can be circumvented by simply not looking).
Also a bit annying that there's no option to show comments other than disabling the addon. :)

Works fine on youtube, but not on twitch right now
also would like to have the fast-toggle-option as with adblock and others otherwise a well done add on

Please add these to block twitch seek bar. When hovering over the seek bar, the little circle that shows at the present time is still visible. These are in ublock origin format.

www.twitch.tv##.slider--no-outline.js-player-slider.player-slider
www.twitch.tv##.player-seek

Works great, would like to have the option to toggle in the toolbar.