Chrome 80+ A cookie associated with a cross-site resource was set without the `SameSite` attribute. It has been blocked

Question

Chrome 80 and up (released on 4/Feb/2020) enforces setting the SameSite attribute (which I downloaded one day early using Chrome Beta to test my site).

It gives my site the following error:

A cookie associated with a cross-site resource at URL was set without the SameSite attribute. It has been blocked, as Chrome now only delivers cookies with cross-site requests if they are set with SameSite=None and Secure. You can review cookies in developer tools under Application>Storage>Cookies and see more details at https://www.chromestatus.com/feature/5088147346030592 and https://www.chromestatus.com/feature/5633521622188032.

I've looked in Application>Storage>Cookies but I have only one cookie set which looks like this:

How do I know which Cookie was blocked and which request it was blocked on?

Does this issue causes a cookie to not be set OR does it cause a cookie not to be sent in an HTTP request?

Does it treat cookies set client side and cookies set server side (using the Set-Cookie response header) differently?

Thanks

Answer 1

See here for more info: https://www.chromium.org/updates/same-site/test-debug

How do I know which Cookie was blocked and which request it was blocked on?

You will need to look through the Network panel in DevTools, find the request, and look at the filtered out cookies.

Does this issue causes a cookie to not be set OR does it cause a cookie not to be sent in an HTTP request?

Both are possible.

Does it treat cookies set client side and cookies set server side (using the Set-Cookie response header) differently?

No.