Hold down the right mouse button and draw an L shape to close the active tab.
To close a tab, hold down the right mouse button and swipe down and right, making an L shape.
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Keep doing that to close multiple tabs one after another. It’s a great and fast option, when you want to see what’s on the page before closing it.
In case you accidentally closed a tab or changed your mind, you can reopen recently closed tabs by holding down the right mouse button and swiping up and right.
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You can discover more gestures and customize them in Settings > Mouse > Gesture Mapping.