Hi Quentin,

I tried to use the -cmd ShowHide command in Unity (Ubuntu 13.10 latest) but it does not work.
Other commands like "Quit" work well.

colonel@jupiter:~$ gmusicbrowser -cmd ShowHide
Found a running instance (using '/home/colonel/.config/gmusicbrowser/gmusicbrowser.fifo')
colonel@jupiter:~$

... provokes Hide successfuly but fails at Showing the window.
-debug option didn't reveal much more info.
Let me know if further investigation I can perform on my side (logs, etc.)

I have similar problems with the IBus integration (MPRIS2) : I shall de-activate shortcuts in Unity and use the keys only while GMB has focus.

Bonne continuation !

Thanks for reporting this, I'll look into this.

Sorry for taking so long, it should be fixed in git.