Hijacks the bottom of the (bottom, if there is such a thing) monitor. The bottom right corner (and, in the unlikely case where your X server doesn't support pressure barriers, only the corner) toggles the message tray. The bottom left corner executes, if enabled, a configured command. By default, the custom command is disabled and can be enabled and changed from the preferences. More information about the preconfigured command is available after installation in ~/.local/share/gnome-shell/extensions/hi-jack/readme.txt.