Tessi, your version is more than sufficient.

You'll have to explain what you mean by JPEGs coded in the .htaccess as WebP.

If you have ticked the WebP option in Web Properties > Websites > Include WebP images, then Xara publishes both JPEG and WebP so you can picked either as WebP is fully rendered in all major browsers for over three years now. Both filetypes are uploaded but are only used when called so you could pick 'n' mix.

Acorn