Although this has gone under the radar in Canny, it has been possible to preview assets for a while. For reference I have attached a screenshot of how to access the preview option. Simply click the arrows when hovering over an asset to view a larger version.

This is something we'll be bringing back as part of a new asset management feature.

It will also allow you to add some meta-data to images and assets, and insert them inline in text fields. You will also be able to re-use them in multiple items.

This should be available in the next few months - really sorry about the friction it's causing in the meantime.