TAB GLUE: Combine separate browser windows into one as tabs
If you have multiple Chrome browser windows open, Tab Glue will turn them into tabs and put them into one browser window. Otherwise, you’d have to drag-and-drop a browser window onto another to combine them, and do so separately for each window. Through a single click, this extension will apply this action at once to all Chrome browser windows on your OS’ desktop. Another extension that does the same thing is Join Windows.