It's a new JavaScript API, meaning that if we remove it, websites relying on it would break. It does not have any other compatibility risks that differ from similar APIs.
Ongoing technical constraints
What technical constraints will be added to user agents implementing this feature?
None.
Will this feature be supported in all environments (desktop, mobile, tablets, TV, eBooks, automotive, etc.)?
According to Chrome UseCounters, 9.3% of all web page loads use WebSocket. That would be a good approximation on the upper bound of web pages that could benefit from this, as WebTransport is functionally a superset of WebSocket.
Intent to Migrate: WebTransport
Working group decision to adopt
If the group is formed, it would be incorporated through the charter: https://w3c.github.io/webtransport-charter/charter.html
Proposal
https://github.com/wicg/web-transport
Summary
WebTransport is an API that allows web applications to establish interactive, bidirectional, multiplexed network connections to a remote server.
Motivation and Use Cases
Detailed in the explainer.
Compatibility Risk
It's a new JavaScript API, meaning that if we remove it, websites relying on it would break. It does not have any other compatibility risks that differ from similar APIs.
Ongoing technical constraints
What technical constraints will be added to user agents implementing this feature?
None.
Will this feature be supported in all environments (desktop, mobile, tablets, TV, eBooks, automotive, etc.)?
Yes.
Link to implementation experience and demos
Chrome has implemented QuicTransport, and is experimenting with it as an origin trial: https://web.dev/quictransport/
Data
According to Chrome UseCounters, 9.3% of all web page loads use WebSocket. That would be a good approximation on the upper bound of web pages that could benefit from this, as WebTransport is functionally a superset of WebSocket.
Security and Privacy
Discussed in https://wicg.github.io/web-transport/#privacy-security
Accessibility
No accessibility implications.
Internationalization
No i18n implication. All of the data path APIs only accept binary input.