Thanks for the useful add-on! IMHO it would benefit users more, if it has "Move to Existing Window" feature. Many users browse separate web topics at once in dedicated browser windows. Sorting Tabs between open Windows would be a lot easier and faster with such feature, especially before Saving select subject Windows to individual Sessions with popular "Session Manager" add-on. Without this feature one needs to reposition and expose each browser window on desktop before dragging Tabs into it, and its cumbersome, slow and messy to achieve on a cluttered with other apps desktop.