An isolated repro of the mechanism I described — a server writing three
SSE frames then going silent with the connection held open, read via
fetch + getReader — delivers every frame in all three engines, WebKit
included. So 'the SSE stream's last message is not delivered' is not a
supported description of the failure.
The keep-alive experiment that appeared to confirm it was one
observation, and the failure is not even stable in shape: two consecutive
webkit runs failed at different stages (ready wait vs connect wait),
which a deterministic buffering bug would not do.
What is unchanged: the App smokes really do fail under Playwright's
WebKit, which is why the engine stays out of the matrix; that reason
never depended on the mechanism. The parseSSE cross-chunk defect also
stands, being read off the code rather than inferred from an experiment.
No behavior change.
Signed-off-by: cliffhall <cliff@futurescale.com>
d493b232b3