Which jetways are you referring to ? Default jetways are operated with CTRL+J, even without GSX. SODE jetways should be operated from the GSX menu, which can be undocked.
Note that, the "GSX menu", is not really a GSX menu. It's the standard Simconnect menu, which is shared between all 3rd party apps that use a menu, and we don't have any control over its size, position, docking status and even keys used. They are handled entirely by the sim.