Blocked Set-Cookie in development environment DRF SessionAuthentication + React

Question

I have a very specific question that I haven't found within the many questions regarding this topic.

Initially my Set-Cookie headers were blocked. I managed to resolve that, but the Cookies are still not stored and I have no clue as to why.

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I have a DRF + React web application which I recently changed from Token Authentication to Session Authentication for server side expiration. In production this works great, upon login I receive two Set-Cookies, a session id and a csrftoken. However, in my development environment, the Set-Cookies are blocked as This Set-Cookie was blocked because it had the 'SameSite=Lax' attribute but came from a cross-site response which was not the repsonse to a top-level navigation..

• I tried changing the SameSite setting to none, in which case Chrome requires secure cookies, which I don't think is possible in my dev environment.
• I tried disabling Cookies without SameSite must be secure in chrome://flags.
• Listing 127.0.0.1 in CORS_ALLOWED_ORIGINS allows Set-Cookie, but somehow an old cookie is set. This does not work for localhost.
• Although I don't think this is relevant, a lot of solutions here mention to add {withCredentials: true} to the requests, this however does not solve my issue as I do receive the Set-Cookie headers, they're just blocked.
• If I log in on 127.0.0.1, I get a 403 with CSRF missing or incorrect. It is listed in CSRF_TRUSTED_ORIGINS and I do not get this on localhost.

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Cookie/CORS related Settings.py

# CSRF / CORS / Cookies
ALLOWED_HOSTS = ['*']
CORS_ALLOWED_ORIGINS = [
    'http://127.0.0.1:3000',
    'http://localhost:3000', 
]
CSRF_TRUSTED_ORIGINS = [
    'http://localhost:3000',
    'http://127.0.0.1:3000',
]
CORS_ORIGIN_ALLOW_ALL = True
CORS_ALLOW_CREDENTIALS = True
CSRF_USE_SESSIONS = False
CSRF_COOKIE_HTTPONLY = False         # Not accessible by client (not important)
CSRF_COOKIE_AGE = 8 * 3600           # Expires after 8 hr
CSRF_COOKIE_SECURE = False           # Only HTTPS

SESSION_COOKIE_HTTPONLY = False      # Not accessible by client 
SESSION_COOKIE_AGE = 8 * 3600        # Expires after 8 hr
SESSION_COOKIE_SECURE = False        # Only HTTPS

Answer 1

Eventually I found the solution, which contains two parts:

1. Make sure Set-Cookie headers aren't blocked by adding 'http://127.0.0.1:3000' to CORS_ALLOWED_ORIGINS.
2. Ensure no old cookies are in the browser during login, so that you can login with the tag {withCredentials: true}. The CSRF check will fail with old/invalid cookies. However, with the check set to false, the new cookies aren't stored.