Applications assigned to All Desktops loses focus when moving through desktops

If I assign an application to all desktops like this:

It loses focus after moving to another desktop and moving back.

Step to reproduce:

1. Assign an app to All Desktops (let's say iTerm).
2. Switch to another App on the same Desktop. Let's say Numbers.
3. Switch back to iTerm. Work on it.
4. Move to another desktop.
5. Move back to the original desktop where you was lastly working on iTerm, expecting to work again on iTerm.
6. When the desktop appears on the screen, the iTerm app seems to have the focus, but after <1 second the previously used app on that desktop (in this case Numbers) get the focus.

This is very annoying. Any idea how to fix this? I'm not sure if is a bug in OSX, I"m using high sierra.

I found that this happens when you have the applications assigned to "All Desktops," or even a particular desktop. When I assigned all of my apps to "None," the focus issue went away. I'm not sure how the setting got turned on, but switching all apps to "None" solved my focus issue.