Based on the Documentation here it looks like Cloudflare does not
HotLink protect WEBP Images.
What does Hotlink Protection do?
Hotlink Protection prevents your images from being used by other sites. This can reduce the bandwidth consumed by your origin server.
When Cloudflare receives an image request for your site, we check to ensure the request did not originate from visitors on another site. Visitors to your domain will still be able to download and view images.
Hotlink protection has no impact on crawling, but it will prevent the images from being displayed on sites such as Google images, Pinterest, etc.
Supported file extensions: gif, ico, jpg, jpeg, and png.
This is really bad as nowadays most websites use the WEBP image format
for performance increases and its usage is skyrocketing.
See here Statistic Data:
Can Cloudflare please support WEBP images for HotLink Protection ?
Thanks in advance for the support!