Double clicking the video feed or pressing the zoom out button on the top right resets it to the current fit view.
Fit views
The button in the top right swaps between the two fit options.Cover view
Click to zoom in and remove all blank space.
Contain view
Click to fit the feed’s native aspect ratio.
Zoom and pan
You can also adjust the video feed directly:- Zoom: scroll wheel
- Pan: left/right mouse buttons, or click-drag the scroll wheel

When zoomed, the zoom scale appears in the top right.