You may have noticed that some themes that used to display the header image on a page or post as the featured image are no longer showing up and defaulting to the primary header. At first this was thought to be a bug with the latest WordPress update but according to WordPress it is actually a bug fix.
WordPress decided that cropping is ok but enlarging the image isn’t. In a staff reply, this was called “a long time standing bug” that has finally been fixed:
“Actually, that has been a long time standing bug with the way we processed images. This has been fixed now. Previously, images that were smaller than what a theme specifies as the size for a featured image would be upscaled and distorted. This should never happen by default.”
The only problem is that there was little communication about this and many people were unprepared for this change.
If you need help getting all your old images sized properly contact us and we can help.