Chrome Version: 71.0.3572.0
OS: ChromeOS Teemo

What steps will reproduce the problem?
(1) Let multiple notifications accumulate (e.g. enable notifications from a site like Facebook, get someone to message you).
(2) Click to show the system menu and notifications.

What is the expected result?

Expect that the accumulated notifications are shown, above the system menu, and that the 'x's are accessible for each of them.

Expect that if there _is_ a scrollbar then it goes away once there are few-enough notifications to all be shown at once.

What happens instead?

Scroll-bar remains shown until you explicit scroll down to the "clear" UI surface and back again. 'x's on notifications are not accessible.

I believe this issue regressed with the system-menu refresh in M70, but I'm not 100% sure of that.