Почему сайт отказывается загружать шрифты?

Сайт написан на MERN стеке, проблема возникает при деплое на Heroku. В проекте используется Helmet

Ошибка:

Refused to load the font '<URL>' because it violates the following Content Security Policy directive: "default-src 'none'". Note that 'font-src' was not explicitly set, so 'default-src' is used as a fallback.


Refused to load the font 'https://fonts.gstatic.com/s/opensans/v18/mem8YaGs126MiZpBA-UFWJ0bbck.woff2' because it violates the following Content Security Policy directive: "default-src 'none'". Note that 'font-src' was not explicitly set, so 'default-src' is used as a fallback.

Я пытался гуглить, но ничего не помогло:

<meta http-equiv="Content-Security-Policy" content="font-src 'self' data: https://fonts.gstatic.com/ https://fonts.googleapis.com/; default-src 'self' https://fonts.gstatic.com/ https://fonts.googleapis.com/">

Настройка Helmet:

app.use(
 helmet({
  contentSecurityPolicy: {
     directives: {
        ...helmet.contentSecurityPolicy.getDefaultDirectives(),
        "img-src": ["'self'", "https:"],
        "script-src": ["'self'", "https:"],
        "font-src": ["'self'", "https:", " data:", "https://fonts.googleapis.com/", "https://fonts.gstatic.com/"],
        "default-src": ["'self'", "https:", " data:", "https://fonts.googleapis.com/", "https://fonts.gstatic.com/"],
     },
  },
 })
);