We currently allow to use PNG images in a lot of places, but these cannot be (lossy) compressed by Cloudflare so end up being more than 10 times as big for the same image. We can restrict the images that can be chosen by file type so that they can only pick a JPG for blocks that are supposed to show photographs (e.g. carousel).

For a sense of scale of the impact. Just a single png photograph on the page can drop the pagespeed score by more than 10 points out of 100.

*Tasks*

• Limit image selection to jpg files on Carousel Header and Gallery Carousel blocks.
• Add an informative message for editors.

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