Something odd is happening with the saturation and contrast in the colours of my thumbnails. Those below look fine in my post edit page but in the media library and in the front, the thumbs look horrible, but the full size images appear with the correct colour both front side and in the media library
My website appears to be applying the Instagram Influencer Unreality filter to the thumbnails it generates from my JPGs. Note the difference in the colour saturation in the blue header on the image above and below. Both images have been output from the same Affinity Designer app, the above is a JPG the lower is a PNG. Note, the bad colour on the thumbs is not present in the full size images in either case. Additionally, the same JPG images uploaded on other WP installations are not suffering the same bad colour thumbs. See https://danceworldmagazine.com/clour-profile-test-2/ and https://graphicviolence.co.uk/workbook/colour-profile-test-3/
Hmmm, looks like I’ve fixed this. Curious.