Not loading .webp anymore

I’ve just installed and tested the plugin with various settings. At some point inbetween it loaded nearly all images as webp, most of them served through rewriting. After I read on the plugin page that it’s recommended to change to CDN friendly operation mode when using Cache Enabler, I tried that – since then most images are back to jpg and I can’t get it to work again. Of course I reverted the setting to “varied image response”, forced rewriting .htaccess, emptied all caches – but now it’s still loading the jpgs. I can even see the converted .webp in the same folder, but it’s loading the jpg (p.e. https://neu.greenpearls.com/wp-content/uploads/resized/7a161ec785627069285f8db8ade93384/hotel-sturm-nachhaltig-urlaub-deutschland.jpg – loading 120kb, while the .webp has 80kb)
What can I do?

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