Fix random browser crash on fullscreen preview

Steps to Reproduce:

• Upload a small PNG image (image attached) to a folder in Nuxeo.
• Click on the Annotations pill.
• Click on the Annotations icon (a notepad).
• Add a polygon annotation.
• Save.
• Open fullscreen preview.
  => Annotation appears, but not image.
• Exit fullscreen preview.
  => Normal-sized preview is missing, annotation is still present.
• Open fullscreen preview.
  => Preview still not showing, annotation still showing.
  => After a few minutes, exit fullscreen and browser crashes.

When the browser was restored and the steps above repeated, the image eventually loaded after ~10 seconds and the browser didn't crash.