This bug is for crash report bp-e6409b61-b854-40e1-b49e-b76d10191018.

Top 10 frames of crashing thread:

0 xul.dll static void mozilla::dom::MediaDevices::EnumerateDevices::<unnamed-tag>::operator dom/media/MediaDevices.cpp:168
1 xul.dll void mozilla::MozPromise<RefPtr<mozilla::media::Refcountable<nsTArray<RefPtr<mozilla::MediaDevice> > > >, RefPtr<mozilla::MediaMgrError>, 1>::ThenValue<`lambda at z:/task_1571348679/build/src/dom/media/MediaDevices.cpp:137:11', `lambda at z:/task_1571348679/build/src/dom/media/MediaDevices.cpp:166:11'>::DoResolveOrRejectInternal xpcom/threads/MozPromise.h:730
2 xul.dll void mozilla::MozPromise<RefPtr<mozilla::MediaRawData>, bool, 1>::ThenValueBase::DoResolveOrReject xpcom/threads/MozPromise.h:489
3 xul.dll nsresult mozilla::MozPromise<RefPtr<mozilla::MediaRawData>, bool, 1>::ThenValueBase::ResolveOrRejectRunnable::Run xpcom/threads/MozPromise.h:402
4 xul.dll nsThread::ProcessNextEvent xpcom/threads/nsThread.cpp:1225
5 xul.dll NS_ProcessNextEvent xpcom/threads/nsThreadUtils.cpp:486
6 xul.dll mozilla::ipc::MessagePump::Run ipc/glue/MessagePump.cpp:88
7 xul.dll MessageLoop::RunHandler ipc/chromium/src/base/message_loop.cc:308
8 xul.dll MessageLoop::Run ipc/chromium/src/base/message_loop.cc:290
9 xul.dll nsBaseAppShell::Run widget/nsBaseAppShell.cpp:137

There is 1 crash in nightly 71 with buildid 20191017215425. In analyzing the backtrace, the regression may have been introduced by patch [1] to fix bug 1397528.

[1] https://hg.mozilla.org/mozilla-central/rev?node=9b14e7bdee7a

I'm duping this to bug 1589854, since that one is already tracked.