A recent Youtube Web update has added a canvas whenever the seek bar is visible, an HTML5 canvas pops up. This was not asked for and not needed. If you disable canvases for privacy, this will cause a horrific red bad to cover half the screen until you hide the seekbar. Canvases can be used for fingerprinting, which I’m sure Google is doing here.
99/100 people will not care. I’m one of them.
For that 1/100: sure it’s infuriating but probably more than mildly.