For example, you can use Kiro without having any AWS account at all. Kiro has social login through Google and GitHub. Basically, Kiro is backed by AWS, but is it's own standalone product, and we hope to see it grow and appeal to a broader audience than just AWS customers.
Redirect back to localhost:3128 is normal, that's where Kiro is watching for a callback, but the missing state is not normal. Something may have stripped the info out of the callback before it occurred, which is why I suspect an extension in your browser.
Will keep an eye on this though!
Then in Kiro I see "There was an error signing you in. Please try again.".
FWIW, I've tried GitHub & Google, in different browsers, on different networks.
I personally run my proxy there and overall I'd take some > 10000 port for such kind of stuff
Or can you join the Discord and message me directly @swaminator