OK.
I use Alfred to open most my apps and to write a lot - shortening URLs, opening apps, checking words on a dictionary, copying and pasting text, etc.
What I noticed is that when I open the Alfred dialog window and type a command (like "Define" to see the dictionary description), even if I don't click enter to open the targeted app (in this case, "Dictionary"), when I come back to the application I was using before (usually a browser where I am writing), if I try to type or paste something, it does nothing and rings the "error" sound. I need then to Alt-Tab to go to other app and then Alt-Tab again to come back to the browser so it "responds" allowing me to type or paste text .
The behaviours is the same to any app opened by Alfred while writing on the browser (usually Google Docs or Spreadsheet, but in some cases the URL field of the browser itself).
Is that detailed enough? 🙂