got a msg from Aras @ Unity that may help in future dev so i thought I’d share the relevant bits:
“Each “window” in the editor has it’s own GL context. At Update() time, probably the current context is the one that got repainted last. It could be scene view, game view, inspector, etc. depending on layout & stuff. If however you’d hook your plugin into something like OnPreRender() of a camera, then the current context should always be game view.”
Not sure if this is useful to Unity Syphon yet.