hehe yes I know, but it doesn't tell which images have been processed and as there wasn't any file with webp extension to be found, I did them all 🙂
Well, after doing them I have no idea what exactly happened. Image sizes are the same, all still with jpg extension (is there any reason to this? I mean that they all end with jpg even though they are png?). No sign of them having changed to webp.
Tried uploading a webp image manually to a product and it tells me webp isn't a valid format :'D But if we look at the statement in the image settings again, it says:
" Serve smaller images in the webp format to browsers that support it "
First of all actually the first post here in this thread was right, it clearly says "smaller images" are being served in the webp format. Might be just incorrectly written.
Second of all else: It says serves. That clearly leaves no indication that any pictures are being changed, it almost sounds as if the pictures are being converted to webp on the fly on page load, which of course shouldn't be the case, but still everything about this is simply unclear, especially because it doesn't seem to work AND I cannot even add a webp image manually to any product.