Exposé App Focus Loss issue macOS Sierra (10.12.6)

When I enter Exposé using any method, I select my desired window and it comes to the forefront, but then focus switches back to my previous app no matter what.

Example:


Doing something in Safari
Use Exposé to switch to Email (not app switcher)
Email comes to the front (or un-minimizes)
Safari comes back to the front


This also happens if I switch between windows of the same app. Meaning, if I switch from one email window to another email window via Expose, Safari again takes focus.

It's a simple bug with Exposé not giving focus to the correct app, but this all works perfectly on my other computer running Yosemite.
This is a bug that occurs when the app in question is assigned to "All Desktops".

Here's a work-around: right click the App in the dock and select Options &gt; Assign to &gt; This Desktop or None.