Comment 60 for bug 438868

I've narrowed down a way to reproduce this on Ubuntu 9.10:
1. Open a Firefox window.
2. Suspend the computer.
3. Unsuspend it back (note: in my case, I have to unlock the screen).

After this, the address bar autocompletion in the previously open window is broken. A way to fix it is to get keyboard focus elsewhere (I use right-click menu on the gnome panel) and then return it to the location bar.

Similar behavior is observed with Eclipse 3.5. In fact, it's worse there, because keyboard presses cease to have any effect when the buggy state is reached.
In an unrelated Eclipse bug, it's been noted that certain changes made in Gtk+ 2.18 may break applications or widget frameworks that are using Gtk+ in weird undocumented ways which happened to work before.