This is a Linux build with the GTK2 toolkit and Xft enabled. It was built on Red Hat 8, so is binary compatible with Red Hat 8 and above (i.e., glibc 2.3.2 or newer, GTK 2.0 or newer, Xft 2.0 or newer). This build does contain Talkback. Build contributed by David Baron (dbaron@dbaron.org), Mozilla Foundation.