Could you please add a Feature-Policy?
This is the one that I am using for more than a year now. (host nginx)
add_header Feature-Policy “geolocation ‘none’; midi ‘none’; notifications ‘self’; push ‘none’; sync-xhr ‘none’; microphone ‘none’; camera ‘none’; magnetometer ‘none’; gyroscope ‘none’; speaker ‘none’; vibrate ‘none’; fullscreen ‘none’; payment ‘none’;”;
Would it make sense to add the following to Content-Security-Policy
header? This is what I am successfully using (added by host nginx, on top of discourse built-in CSP):
default-src 'none'
style-src 'self' domain 'unsafe-inline'
img-src https://*.domain.org data: blob: 'unsafe-inline'
font-src 'self' domain
connect-src 'self' domain
manifest-src 'self' domain