There is no way to do that now. But, if you want to add settings for it, please feel free to commit changes.

I would like to avoid settings as much as possible... it should be automatic (e.g. resolution close to 32:10 is probably a dual monitor).

In the end I modified directly GTSpotterGlobalShortcut class>>#openGlobalSpotter, however it's not generic (so I am not going to commit it yet).

As I found, there are more things that do not play well with dragging Pharo over two monitors: (GT)Debugger, taskbar, growl, ... and possibly many others, so maybe some dual-monitor care package will emerge as I will fix the issues one by one.

Peter