Comment 2 for bug 1444509

i can repro this reliably on Xubuntu 18.04 with remmina 1.2.0-rcgit-29:

- open 'Mousepad' (or some other simple app.
- open an RDP session to a remote machine.
- DISABLE 'Grab all keyboard events' for the new session
- position the windows so the 'Mousepad' window partially overlaps the remmina session window, like this:

  +----+
  | |--+
  | x| |
  +----+ |
    | |
    +-----+

- bring the 'Mousepad' window to the front
- click in the 'Mousepad' window in a location where that window overlaps the remmina session window.. 'x' in the above picture (this sounds strange, but it's necessary)
- alt-tab to the remmina session