Firefox built for Gtk3 toolkit.
It's based on latest mozilla-central repository (nightly builds) and patches from Firefox Gtk3 project at mozilla (https://bugzilla.mozilla.org/show_bug.cgi?id=627699) and some other ones.
It's highly unstable and experimental. Use a new profile for the run, you can create it by $firefox -ProfileManager.
If you see any bugs, please file them at bugzilla.redhat.com under firefox component with [GTK3] in summary.
Some knows issues:
This package can be installed long the official Fedora packages. Run it by firefox-gtk3 or by icon from menu.
The following unofficial repositories are provided as-is by owner of this project. Contact the owner directly for bugs or issues (IE: not bugzilla).