cuelang.org: delay displaying the site header until the user scrolls some distance

[jpluscplusm]

One more thought: right now the header reappears as soon as I scroll up by a single pixel. I reckon it should take a little bit more than that, because otherwise it reappears extremely easily - for example, when I scroll down with my fingers, sometimes I'm not perfect and I scroll up by a few pixels at the start or end, due to the nature of how my fingers move. This can make the header re-appear when I don't want it to, causing a bit of frustration as it eats into my reading space.

Originally posted by @mvdan in #3058 (comment)

[jpluscplusm]

We can add some logic that will show the header on scroll up after x pixels are scrolled (100 or so?)

Originally posted by @JorindeUsMedia in #3058 (comment)