About the canvas view settings
The canvas displays a preview of the video at the location of the playhead on the timeline. Use the following canvas view options when editing your video:
Change the canvas preview scale:
To preview how the final video will look at the current canvas dimensions, set the canvas preview scale to 100%. Click the dropdown and select a percentage or use two-fingers to scroll up or down on the trackpad.
To move or pan the canvas:
Hold down the spacebar and click and drag the video area on the canvas. For best results, set the dimensions of the canvas to the recommended dimensions for your intended sharing destination, see Change canvas size.