autocomplete on big sur

[ksherlock]

• scrollbar background wrong
• vertical scroller never disappears (and content height is too tall?)
• x to clear not centered.

[ksherlock]

el capitan ... suspiciously similar, though different.

[ksherlock]

fixed via 3bf2f63bf67334225fe48612e49b0071390a3b5e and f14b291e60013a5c8977c6ca095493eaa493d080