Reading https://darekkay.com/blog/avif-images/ and, interestingly, my RSS reader shows “This image is not supported in your browser” for the WebP image, too. But it is; I’m using the latest Firefox. (What I think is happening instead, is that my reader strips away `source` tags.)
@jan Which RSS reader did you use? I'm getting the same issue in Inoreader. I've inspected the embedded image and Inoreader seems to transform the picture element and strip everything apart from the img tag. As img is the "not supported" fallback, this explains the wrong image.
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