Navigation in "mobile" menu has unstable mouseovers.

[markscheel]

If I narrow my browser window horizontally, the top navigation area disappears and is replaced by a hamburger icon in the upper left, which is fine.

But then when I click on the hamburger icon and move my mouse over the menu, putting my mouse anywhere about 2/3 to 3/4 of the way down generates a rapid flickering. Looks like an infinite loop where my mouseover triggers a change in the menu, and then since my mouse is over the changed menu it triggers another mouseover event which goes back to the first menu, and flickers back and forth ad infinitum. All with my mouse completely stationary.