The contextCreated spec defines the following "remote end subscribe steps": > The remote end subscribe steps, with subscribe priority 1, given session, navigables and include global are: > For each navigable in navigables: > Recursively emit context created events given session and navigable. Spec: https://w3c.github.io/webdriver-bidi/#event-browsingContext-contextCreated (The remote end subscribe steps are at the bottom of the section) WPT Tests: https://wpt.fyi/results/webdriver/tests/bidi/browsing_context/context_created/subscribe_steps.py?label=master&product=chrome%5Bexperimental%5D&product=firefox%5Bexperimental%5D&product=safari%5Bexperimental%5D&product=wpewebkit&aligned (Note: The tests for this are being imported in bug301583)