Workaround Rated 5 out of 5 stars
A previous reviewer wrote:"Does not work with FF18, it just opens up the Google Homepage and no results (even the input box is locked)."
I noticed that behaviour. It happens very rarely, but it is annoying when it does as all subsequent searches will fail.Fortunately, I found a workaround:
Whenever that happens, type something into the google input box and hit enter. Even if the box is messed up and does not show the typed characters, it will still work.
Apparently this will cause the add-on to resume working.
Edit: Stopped happening.