I have few machines here and I want to keep the settings and all other stuff (addons, plugins) synced between them. I am using LastPass for passwords and XMarks for bookmarks so this is not an issue. They are always synced. However the addons and settings… I didn’t wanted to redo them all. Wanted to have them cloned. Easiest way for me is to copy the ~/.mozilla folder from one computer to another… This time I ran into bit of a trouble. Settings came from a machine running KDE4. Black fonts over a grayish background. They were copied into the Gnome machine where the theme looks slightly different. Its a black textured background with a whiteish text on it.
When I copied the settings I got all the menu bar items messed up. Black font / black background. Not visible. I managed to fix it. I have opened Nautilus and I have maneuvered to the ~/.mozilla/firefox/123QWE89.default/chrome/ folder and I removed all the files from there.
Reopened the Firefox and it got adjusted to work with the Gnome theme. Fonts got whitish color and I could read “File“, “Edit” and other menus again.
Hope this helps somebody someday.