First milestone only: can an ordinary web page even claim a reader interface? This page enumerates USB descriptors and attempts one interface claim. It never sends APDUs, performs data or control transfers, powers a card, asks for a PIN, signs anything, or reads USB serial numbers. A permission grant is not proof of usable card access.
Checking...
The browser shows its own device chooser. Cancelling it is a normal outcome and is reported below. Nothing happens until you click.
No device selected.
Pick the reader interface, then attempt the claim. The exact stage and exception name are
reported. Interfaces whose class is on the WebUSB protected list (for example Smart Card
0x0B) are expected to fail with SecurityError on an ordinary page.
Idle.