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1. Open SFU client example in browser, for example https://demo.flashphoner.com:8888/client2/sfu/examples/client/main.html, enter server URL, room name, pin code and user name, then click Enter
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Solution: there is the Chromium bug, a stream capturing from a screen window should be publihed in only one quality (no simulcast) until this bug is fixed (in Chrome build 98.0.4736.0)