Raven doesn't send events in Firefox extension

I’m using Raven for a WebExtension. It works perfectly on Chrome however on Firefox for every request sentry sends “Missing required attribute in authentication header: sentry_secret” back.

For more context this’s my setup for Raven:


If I would use privateDNS everything seems working however I don’t want to expose private info to public.

Can anybody suggest how to fix the problem?
Thank you!