No sure I agree on fast. At least on mobile the sidebar has an show/hide slide animation that takes a sizeable fraction of a second. In fact is one of the slowest animations for this I have seen.

I disable animations entirely on devices I use where possible. They just waste time and that adds up if you use something regularly.

I haven't looked at it on mobile, that's unfortunate to hear. I don't see any animation when interacting with it on a desktop browser, snapping open a left side header menu item to see sub-items seems instant.

I meant showing/hiding the side bar itself, not headings in it. Using the triple dash menu button in the top left corner.

Yeah, I see what you mean now, I am looking at it on mobile and that animated slider to show or hide the entire menu seems like it takes unnecessarily long.

Indeed, and any animation at all is too long for UI elements in my opinion.

It should take time for you too appreciate the main text becoming blurry and unreadable and to prepare your brain for the new batch of text

Gonna go out on a limb here and say css transitions are not what they are talking about.

Agreed. Is there an easy way besides the simple OS feature ?