This pull request adds a very simple ad-hoc ListenBrainz widget to the frontend web view, with progressive enhancement (in all fail states it just falls back to rendering the field as normal).
This necessitated adding the ListenBrainz API endpoint to the `connect-src` part of our Content-Security-Policy header. We might want to tweak this to only add that endpoint to `connect-src` for profiles, and then only for profiles that include a ListenBrainz field, but this would require significant dicking about with the middleware, and checks inside the app logic, such that it might not be worthwhile (after all, we control all the scripts right now anyway).
Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4184
Co-authored-by: tobi <tobi.smethurst@protonmail.com>
Co-committed-by: tobi <tobi.smethurst@protonmail.com>
* Set frame-ancestors in the CSP
This ensures we can't be loaded/embedded in an iframe. It also sets the
older X-Frame-Options for fallback.
* Disable MIME type sniffing
* Set Referrer-Policy
This sets the policy such that browsers will never send the Referer
header along with a request, unless it's a request to the same protocol,
host/domain and port. Basically, only send it when navigating through
our own UI, but not anything external.
The default is strict-origin-when-cross-origin when unset, which sends
the Referer header for requests unless it's going from HTTPS to HTTP
(i.e a security downgrade, hence the 'strict').
