Enabling 3DS on the Square Payment Plugin makes it refuse to authorize all payments. I have tested on 4.20 and 4.30 beta. Any idea what could be causing this, or how I could debug it? There aren't any error messages.
We updated the Square SDK to 2020-03-25 (Latest) version. 3ds work correctly on our accounts. You can see changes here. Also you must make sure that you are using the latest API version in your square application. You can test the 3ds in the sandbox, check the Square documentation.