I can't see an image in Safari

As of Safari version 14.1.2 (in macOS version Big Sur) it could happen that the image of a document doesn't load at all.
We already created a fix for this, but there is still an action that needs to be performed in order to have it work completely again. Please follow these steps:

1. Open Safari
2. Go to "Safari > Preferences > Advanced"
3. Enable the developer tools
4. Go to "Develop" in the menu bar on top
5. Hover over "Experimental features"
6. Make sure there is no checkmark in front of "Incremental PDF loading"