I develop custom websites and host them on an NGINX server where I have full control. Some time ago, Google announced that Chrome will be blocking all third-party cookies that do not have SameSite=Lax or SameSite=Strict. Indeed I can see these warnings popping up in my Developer Tools for every site on this server. For example:

Reading third-party cookies is blocked

Name                        Domain & Path
__Secure-3PSID              .google.com/
__Secure-3PAPISID           .google.com/
NID                         .google.com/
1P_JAR                      .google.com/
__SEecure-3PSIDTS           .google.com/
__Secure-3PSIDCC            .google.com/

Setting third-party cookie is blocked

Name                        Domain & Path
_GRECAPTCHA                 www.google.com/recaptcha

In NGINX I have tried adding the SameSite=lax or SameSite=strict attribute to my cookies using the location block, such as:

 location / {
    proxy_cookie_path / "/; secure; HttpOnly; SameSite=lax";
 }

However, this has no effect on these cookies at all. I am wondering if this is something Google has to change on their end? It seems weird that they would be blocking their own cookies, though – and I’ve seen some sites hosted elsewhere which also use Google services such as Recaptcha and Google Tags and do not have this problem.

I have read over Google’s documentation on this topic, watched all the tutorial videos, etc. but none of them give any specific how-to type advice – it’s all very esoteric and vague.

Has anyone else run across this problem before? Any ideas how to address it?