I disabled Photon from the Jetpack settings in the Dashboard to get rid of this issue. It was also resizing many of my images in posts to thumbnail size. When I disabled Photon the error messages and the resizing problem went away.
Jetpack –> Photon –> Learn More –> Deactivate
(It would be nice if a deactivate or disable button was next to each Jetpack feature instead of having to click “Learn More” to find it).
Also from another thread:
“This error displays if you have image in your content editor that has width and height defined.
Until this if fixed just remove width and height from images in your editor and the error is gone.”
