The image viewer is not a separate feature but a feature that is embedded in Typed's split-viewer.
A toolbar specifically for images appears when you click on an image file to be viewed in the split-viewer. The toolbar contains:
Zoom - In and Out
Rotate - Left and Right (90 degrees in either direction)
Image reset
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The image reset allows you to view the image as normal before any view changes have been made.
If you are using a trackpad, the image viewer also allows you to intuitively pinch-zoom in and out on the images.
Place two fingers closely and spread them apart on the trackpad to ZOOM IN
Place two fingers apart and bring them in on the trackpad to ZOOM OUT
