Credentials auth stopped working, ss-generated page now displays

My credentials auth has worked for a long time, but recently stopped working. The service itself is returning a 200, and a servicestack-generated page that I haven’t seen before that looks like the attached. There are also no cookies being saved.

I do have this line in my AuthFeature initialize:
AllowGetAuthenticateRequests = req => true

some further information, I believe that auth no longer working has something to do with Chrome’s cookie behavior changing in version 84 (as documented here. The version of Chrome I upgraded to is reporting that it will not save the cookies because SameSite=None and Secure=false. I have attached a screenshot below

What version of ServiceStack are you using and what’s your SetConfig() configuration?

version 5.9.0

  SetConfig(new HostConfig
            DebugMode = true,
            StrictMode = false

(is that the only config you wanted?)

Change it to enable same site cookies:

SetConfig(new HostConfig {
    DebugMode = true,
    StrictMode = false,
    UseSameSiteCookies = true