switching windows by alt+tab back and fort causes loosing focus from element and focusing on the main menu [#16231]

[Macarena]

Dear devs,

in build 2219:

switching windows by alt+tab back and fort (MM5 and any other opened window, it was a Firefox Quantum browser at me) causes loosing focus from element and focusing on the main menu - the way the alt key would make it. That happens only every other time, only every other switch.

M

[Ludek]

Hi, thanks for reporting,
I see the same, tracked as https://www.ventismedia.com/mantis/view.php?id=16231