I don’t know what has happened but my toolbar in Firefox has gone a horrible bright Raspberry colour.
Any advice to change it back to s proper colour appreciated.
Ubuntu 10.10 Firefox
BTW it’s not a Christmas theme as my other Ubuntu computers have no change.
In Firefox, try adding a theme, then reverting to the Default Theme. (Tools>Add-Ons>Themes)
Beyond that you could rename the hidden ~/.mozilla directory to something like ~/.mozilla.old
Be Aware - doing this will cause you to loose your bookmarks and plugins etc.
so you might want to export your bookmarks first…
Hit Ctrl+Shift+O to open the bookmark manager, then select backup, and save them somewhere as a .json file
Rename the ~/.mozilla file with:
mv ~/.mozilla ~/.mozilla.old
Close any running instances of Firefox, and restart it… ~/.mozilla will be re-created, and Firefox should now be back to defaults.
Import your bookmarks from the Ctrl+Shift+O bookmark manager.
Get any plugins you had again.
In a worst case scenario, you can delete/rename the new ~/.mozilla folder, and rename ~/.mozilla.old back to ~/.mozilla and everything will be back to the way it is now.
Also be aware, you can do the renaming of the hidden .mozilla folder in the GUI (instead of from the command line) by opening your Home folder, then hitting Ctrl+H to make the hidden files/folders visible, then right-clicking the .mozilla folder and selecting Rename.
Cheers Mark
Or … just install Chrome instead … 
It turns out that when I updated Adobe flash it decided to install it’s own theme! I have now reverted to default.