File:Firejailed firefox startup view.png

Summary
Screenshot showing Firefox 52.4.0 running inside an X11 sandbox (Xephyr + firejail, with Openbox window manager). The sandbox has just been opened and the Xephyr window is at its default size. The main ("parent") desktop is running GNOME 3.22.2. Uploaded for use in a forthcoming mini-guide on X11 sandboxing (an addendum to Sakaki's EFI Install Guide).