UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.94 Safari/537.36

Steps to reproduce the problem:
(Working on a script to repro, but for now...)

1. Arrive in the morning and unlock screen; overnight a calendar alert has fired (calendar is in primary window), but isn't visible. I do NOT use desktop notifications for that account/calendar.

2. Click anywhere in non-primary chrome window, no interaction occurs; pointer never changes from default pointer no matter what is under the pointer.

3. Can interact with tabs of primary window, but can not reload calendar tab (i.e. spins forever, never clears calendar rendering).

4. Can use window manager to close stuck chrome windows, and can use History to re-open the recently closed windows, but they're still stuck.

What is the expected behavior?
If an alert has fired, it should still be visible, else it should not be blocking interaction with chrome.

What went wrong?
Alert is not visible, but apparently has grabbed or blocked all input.

Did this work before? Yes Before I upgraded to the new stable release earlier this week (one or two days previously).

Chrome version: 50.0.2661.94  Channel: stable
OS Version: 3.13.0-85-generic
Flash Version: Shockwave Flash 21.0 r0