As validStreams.append() occurs after checking if the track exists already, existing tracks will incorrectly be assumed to be invalid and purged.
Pull request: https://github.com/WebKit/WebKit/pull/23164
Committed 273492@main (dcb7727e3ae7): <https://commits.webkit.org/273492@main> Reviewed commits have been landed. Closing PR #23164 and removing active labels.
<rdar://problem/121589799>