The media card's download link uses artifactUrl's download option so a video or audio output is saved rather than opened inline, and the E2E seeds the thread snapshot with fresh response headers so the patched body is read. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01MRtGG9ARfqqhma3t85Ro2u