Missing icon Bewertet mit 5 von 5 Sternen

Sometimes the address bar search icon disappear, if reset the options then is OK.
Firefox 20 in all my 3 PC with XP, Windows 7 32 bit and 64bit.
I use also RSS icon in url bar addon, maybe there is compatibility problem?

Diese Bewertung wurde für eine vorherige Version des Add-ons ( abgegeben. 

Might be. Does it happen when you open Firefox or after it has been left running for some time? Could you email the addon that you think is ot compatible? Thanks.