Strange F10/Ffx trouble

[Beartooth]

        I'm running Firefox 3.0.8 under Fedora 10. Suddenly, when
I try to type into it anywhere, such as for instance to post to a
web forum, nothing shows up -- till I get the cursor out of the  
box I'm typing into. Then it does.
  
        What could be wrong??
  
-- 
Beartooth Implacable, Curmudgeonly Codger Learning Linux
On the Internet, you can never tell who is a dog --
supposing you care -- but you can tell who has a mind.