CSS `zoom` doesn't rescale viewport units, so the 100vh app root left an empty
strip below the UI when zoomed under 100%. Counter-size the app root to
(100/z)vw × (100/z)vh so that, after the zoom scales it back down, it exactly
fills the window again. Zoom still applies to the whole document so portalled
menus/modals scale with it.
rouggy
6a1103bf5f