[Testing Steps] 1. TV and Fennec link to same network domain 2. Fennec cast a video to TV 3. Press fling button on Fennec [Expected result] Video on TV should keep playing [Actual result] Video will be closes [Error Log] V/GonkBufferQueueCore( 4769): freeBufferLocked: slot 63 V/GonkConsumerBase( 4769): ~GonkConsumerBase W/AudioFlinger( 164): Thread AudioOut_2 cannot connect to the power manager service E/AudioFlinger( 164): no wake lock to update! I/Gecko ( 4769): I/Gecko ( 4769): ###!!! [Child][OnMaybeDequeueOne] Error: Channel closing: too late to send/recv, messages will be lost I/Gecko ( 4769): I/Gecko ( 170): [Parent 170] WARNING: '!IsSessionReady()', file /home/hellfire/workspace/github/gecko-b2g/dom/presentation/PresentationSessionInfo.cpp, line 283 I/Gecko ( 170): [Parent 170] WARNING: 'NS_FAILED(info->Close(NS_OK, nsIPresentationSessionListener::STATE_TERMINATED))', file /home/hellfire/workspace/github/gecko-b2g/dom/presentation/PresentationService.cpp, line 614 I/Gecko ( 4769): [Child 4769] WARNING: MsgDropped in ContentChild: file ../../../../gecko-b2g/dom/ipc/ContentChild.cpp, line 2293 I/GonkMemoryPressure( 4769): Observed XPCOM shutdown. I/Gecko ( 4769): [Child 4769] WARNING: Something is holding on to graphics resources after the shutdownof the graphics subsystem!: file /home/hellfire/workspace/github/gecko-b2g/gfx/layers/ipc/ImageBridgeChild.cpp, line 646 F/MOZ_Assert( 4769): Assertion failure: IsIpcClosed(), at /home/hellfire/workspace/github/gecko-b2g/dom/media/systemservices/MediaSystemResourceManager.cpp:111

Hi SC, Can you help to check this issue? Thanks!

This is by design and aligned with the behavior for video fling on chromecast and roku.

Hi Jack, Tori, Is this also defined in UX spec?

This is not defined in ux spec but in early discussion with SC, we agreed to align the chromecast and roku cast behavior on Fennec.

Close per comment 2,4.