I can't manage to run my app with headless chrome that uses EME `window.navigator.requestMediaKeySystemAccess()`.
For instance, clicking on "Make available offline" in this example app (not mine) will work in Desktop Chrome (as long as the user hasn't deactivated chrome://settings/content/protectedContent in their settings), but not on headless chrome:
Calling `window.navigator.requestMediaKeySystemAccess()` throws a DOMException `Unsupported keySystem or supportedConfigurations`
I couldn't find any documentation stating that these extensions are disabled in headless mode. Maybe I need a flag? How can I know why is it being rejected? For this example, I launched headless mode with: