I’m building an Angular application that is using OAuth2 Auth Code w/PKCE. The app uses hidden iframes to silently renew access tokens. I found that when the OAuth2 authorization serve redirects the iFrame to {parent origin}/silent-refresh.html with a 302, Firefox does not send any cookies set with SameSite: Lax. SameSite: None cookies are sent as expected. I compared this with IE and Chrome and both of those browser send the Lax cookies on when redirecting due to a 302. This problem seems to only occur when the iFrame is being redirected via 302 from a different origin. I.e requests from a basic iFrame to the parent page origin send Lax cookies with no problem. Anyone experience this? Is this expected behavior for Firefox? Firefox Version 68.8