Adding "Content-Security-Policy" is causing a missing image when viewing using Ionic View app

I used the basic sidemenu app for testing after having this issue with the app I’m developing.

When I don’t have a “Content-Security-Policy” tag, uploading and viewing using the Ionic View App shows the instructions for the “3 finger” swipe.

As soon as I add one, even:
content=“default-src *;”

Then the image doesn’t load:

What do I need to add to my Content-Security-Policy to make this graphic work?