Chrome Version: ToT on April 5 (M-67)

The content Window (and hosted UI overlay) do not correctly handle loss of hover.  On both window types, it's possible to hover an element near the edge of the window, then quickly move off the element, leaving the element showing its hovered state.

What steps will reproduce the problem?
(1) Enter VR, go to permissions.site, and scroll the page until there's a permission button partially hidden at the bottom edge of the window.
(2) Hover on the button (it'll highlight).
(3) Move off the bottom edge of the button/content.

The button should naturally un-highlight, but sometimes, it stays highlighted.  Content appears to be unaware of the loss of hover.

The same can be done on a permission pop-up - either of the the Allow or Block buttons may stay highlighted if the reticle moves away quickly enough.