Content is not rendered—there is no browser here—but everything the
extension side does is observable: the HTML it set, the messages it sent, and
whether it cleaned up. Messages travel both ways, so a typed RPC channel can
be driven end to end against the extension-host side of the port. This does
not validate the browser client's acquisition of the VS Code API.
Creates a fake webview capability.
Content is not rendered—there is no browser here—but everything the extension side does is observable: the HTML it set, the messages it sent, and whether it cleaned up. Messages travel both ways, so a typed RPC channel can be driven end to end against the extension-host side of the port. This does not validate the browser client's acquisition of the VS Code API.