If you are on an Android version older than 7.1, then you will still get 600 errors. This problem is outside of my control, and there is nothing I can do to fix the 600 errors for everyone. I can either fix the 600 error for: - Users using any version of the game with Android 7.1+ OR - Users using any version of Android with version 1.14+
Right now, there are still far more users using an older version of the game than users on 1.14+. So I'm prioritizing those users, fixing the 600 errors for them at the expense of users on old versions of Android. In the coming month, most users will get upgraded to 1.14, and I'll switch to option 2. This switch will happen automatically sometime in November (I don't know exactly when).
In the meantime, the only way to fix it would be to update your phone.
@TheDukeOfDank(View Post) I received a report that it's still not fixed, but I am not currently looking into it at this time. Sorry about that .. but I just don't have the time to investigate.
I can confirm that powdertoy.co.uk's certificate should be trusted by Android phones now, because it regenerated and the hack we applied went away. This means we should now be in the 2nd condition I mentioned: "- Users using any version of Android with version 1.14+". I can't explain why it's still not working though.