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Solution: turn off hardware acceleration in the browser, switch the browser of the server to use the VP8 codec.
5. In some Chrome Canary builds H264 Chromium based browsers (Chrome, MS Edge) video is not publishing from canvas when hardware encoding acceleration is enabled
Symptoms; ther is no video in a stream published from a canvas, but there is audio only, streaming fails with Failed by Video RTP activity error
Solution: disable hardware acceleration in browser by setting or publish VP8the flag chrome://flags/#disable-accelerated-video-encode to Disable or use other browser
6. Canvas capturing may stop while switching to another browser tab or minimizing browser window
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