Sid, GNOME 3: Alt-F2 stopped working

[Brian Flaherty <bxf4@yahoo.com>]

For a week or so, Alt-F2 (run a command) won't run anything. If I just 
type a command such as "xterm", it says command not found. If I press 
Escape after this, the pop-up window disappears. If I type the full path 
to the executable (e.g., /usr/bin/xterm), the pop-up window freezes and 
the shading remains. The mouse still moves, keyboard input works in 
other windows, but the bar at the top of the screen is unresponsive.

Seems like a bug, but I wanted to raise it here first and also thought 
maybe someone would have some ideas about what might be going wrong.

I'm not sure, but I also think gnome-do stopped working around the same 
time unfortunately. I like those key combinations.

Thanks for your time.