The Web Smart Card API has been shipped in Chrome on ChromeOS as of M143.
- Provision a ChromeOS device and ensure it's updated to Chrome 143 or above.
- Install the Smart Card Connector extension (this is the PC/SC provider on ChromeOS).
- The API should be available for Isolated Web Apps now. You may wish to try out the provided example.
A rudimentary flow is similar to the native PC/SC libraries. Examples of code can be found in the explainer—for example here is a section on transmitting a command to a smart card reader—and in the aforementioned demo application.