This provides features to handle multiple tabs at once, for example, close them, reload them, and so on. When you press the mouse button and drag over tabs (you should wait a while to start drag after you press down the button!), they are selected. After you release the button, the popup to choose command will be shown. Of course, you can toggle selection by Ctrl-click on each tab and call features from the context menu. Yes, the behavior looks like Excel.