1. Open one editor window.
2. Split one of editor window
Now it is possible to open editors in desired tab group and move editors between the tab groups.
Unfortunately I cannot find any way how to open an editor in more than one of the existing tab groups. I use the multiple editor windows for an imediate preview during editing HTML files.
It would be nice to provide possibility of splitting editor window to any of existing tab group.
It would be also fine to alow rearranging editor windows using drag& drop.