Trying to play Widevine with no Windows Media Foundation (nor Silverlight fallback), see https://support.mozilla.org/kb/fix-video-audio-problems-firefox-windows
Windows Media Foundation(또는 Silverlight 대체)없이 Widevine 실행을 시도하였습니다. https://support.mozilla.org/kb/fix-video-audio-problems-firefox-windows를 참고하세요.