Version: 54.0.2840
OS: Mac OS X

What steps will reproduce the problem?
(1) Open DevTools, undocked into separate window
(2) Open the DevTools drawer with 'Esc' and notice the 3-dot menu in the bottom left
(3) Focus another window
(4) Double click the DevTools drawer's 3-dot menu

What is the expected output?
3-dot menu should still work

What do you see instead?
Any real context menu in DevTools triggered from a click no longer works.

My guess is that there is some issue that is the root cause for this behavior in DevTools.  Alternative repro case:
https://bugs.chromium.org/p/chromium/issues/detail?id=655556

When DevTools receives a click event on the menu button, it calls InspectorFrontendHost.showContextMenuAtPoint(), leading to ContextMenuController::showContextMenuAtPoint().  For some reason, immediately after the window is focused, calling this function twice (double clicking) triggers a bad state.