After updating to Jetpack 10.9.1 (or more if this hasn’t been fixed) you may find that your embedded posts have blank images all of a sudden.
This is what I found happening with my Understrap child theme today suddenly showing ”Data:image/Gif;Base64″ as an image source.
This is due to Jetpack’s Lazy loading (which for some reason suddenly started acting weird).
The only fix I’ve found so far is the simple one of disabling Jetpack’s lazy image loading.
If you figure out a fix so I can re-enable lazy loading let me know in the comments below!
Edit: Some old support solutions recommend uninstalling and reinstalling Jetpack to solve this issue!
As shown here: https://github.com/Automattic/jetpack/issues/10301
Edit 2: I found a solution!