I've developed an app in Python Flask and deployed it with Nginx and uWSGI. On login page in Firefox Facebook login button is not showing and I get an warning message in console: Content Security Policy: Ignoring “'unsafe-inline'” within script-src: ‘strict-dynamic’ specified Content Security Policy: Ignoring “https:” within script-src: ‘strict-dynamic’ specified Content Security Policy: Ignoring “http:” within script-src: ‘strict-dynamic’ specified I've tried setting CSP config on nginx and in flask using Flask-CSP but the problem is still here. Facebook SignIn works on all other browsers and Google Sign in works in all browsers including Firefox