RewriteCond %{HTTP_ACCEPT} image/webp
RewriteCond "%{DOCUMENT_ROOT}/wp-content/cache/wp-rocket/%{HTTP_HOST}%{REQUEST_URI}/.no-webp" !-f
RewriteRule .* - [E=WPR_WEBP:-webp]
<IfModule mod_headers.c>
Header append Vary Accept env=REDIRECT_accept
</IfModule>
AddType image/webp .webp