Can't assign to "all desktops"
 

I make heavy use of Apple's spaces/desktops feature and am frequently switching between desktop views. I like to be able to view omnifocus on all of these views, and so I've tried assigning Omnifocus to "all desktops" from the dock, but when I click on the Omnifocus icon, it always switches me to the desktop screen on which omnifocus is open, and it never switches to the current desktop. The expected behavior is that Omnifocus switches to the desktop that I am currently on (for example, 1Password does this).

Is there anyway to get this working? It's rather a pain to have to drag omnifocus back and forth between desktops just so I can look at omnifocus while I'm doing other things.