Content-Type header missing for WebP images
The Content-Type
header is not set for WebP images.
SEO-optimization-tools complain about the missing header.
I tested this with Apache, I'm not sure if this also applies to nginx.
The reason for the missing header is probably that Apache and/or Ubuntu does not know the WebP mime-type.
The /etc/mime.types
file on Ubuntu 20.04 contains no entry for WebP.
The header can easily be set with an entry in the .htaccess
file:
<IfModule mime_module>
AddType image/webp .webp
</IfModule>
It should be discussed if the change should be made to the QUIQQER .htaccess
file or if administrators should make that change manually as it can also be achieved by editing the vHost or probably the system configuration.