WebRTC video stream is not playable in Opera browser

[cupuyc]

I can see my published WebRTC stream in Chrome via Red5Pro admin panel at: https://red5pro.server/live , but can't see it under Opera (both Mac and Win).

I see error in console:
Error in subscribing to stream - Error in stream subscription: Session start failed for localhostStream--329

It is strange, because Opera uses engine from Chrome, then WebRTC should work smoothly.

Browser console log shows:

2017-11-23T10:52:08.752Z - [red5pro-sdk] debug: (RTCSubscriber) [onsocketicecandidateend]
r5pro-subscriber-failover.js:114 [Red5ProSubscriber] WebRTC.IceTrickle.Complete.
red5pro-sdk.min.js:9 2017-11-23T10:52:08.752Z - [red5pro-sdk] debug: (RTCSubscriber) [sendsubscribe]
red5pro-sdk.min.js:9 2017-11-23T10:52:08.753Z - [red5pro-sdk] debug: (R5ProSubscriptionSocket) [websocket-post]: {
  "subscribe": "localhostStream--329",
  "requestId": "subscriber-4983"
}
red5pro-sdk.min.js:9 2017-11-23T10:52:13.077Z - [red5pro-sdk] debug: (R5ProSubscriptionSocket) [websocket-response]: {
  "data": {
    "type": "error",
    "message": "Session start failed for localhostStream--329"
  }
}
red5pro-sdk.min.js:9 2017-11-23T10:52:13.078Z - [red5pro-sdk] error: (RTCSubscriber) Error in stream subscription: Session start failed for localhostStream--329.
[Optional detail]: undefined
r5pro-subscriber-failover.js:114 [Red5ProSubscriber] Subscribe.Fail.
r5pro-subscriber-failover.js:180 [subscriber]:: Error in subscribing to stream - Error in stream subscription: Session start failed for localhostStream--329.