The scroll-edge fade was a gradient div tinted with the surface colour, laid
over the tabs. Tabs paint their own fills, so at an edge that washed a pill
toward the surface colour instead of dissolving it, and it was only correct
while whatever sat behind the strip was exactly that colour. A mask fades pill
and label together to real transparency — the way the command palette fades its
results, and the way every other horizontal fade in the app is drawn. The ramp
goes to 24px, close to the palette's, since a short one reads as a cut.
The tab chip drops to 26px, leaving 7px above and below instead of 5px. The
collapse toggle and the action buttons stay 30px: a tab paints a fill so its box
is visible and wants air, where those are bare glyphs whose box only shows on
hover.
The close button now centres itself rather than encoding (band - 24) / 2, which
would have put it off-centre the moment the band changed.
Waleed
4c8fec1a41