O vídeo carrega, mas é possivel ouvir apenas o som, acompanhado por uma tela preta. Dando uma olhada no console parece que o navegador está gerando erros ao rodar qualquer midia de vídeo: "Content Security Policy: The page’s settings blocked the loading of a resource at self (“style-src”). normal:1 Loading failed for the <script> with source “https://f.vimeocdn.com/p/2.74.14/js/player.pt-BR.js”. pt-br:1 Loading failed for the <script> with source “https://www.googletagmanager.com/gtm.js?id=GTM-RBKK&l=_gtm”. pt-br:1 Loading failed for the <script> with source “https://www.googletagservices.com/tag/js/gpt.js”. pt-br:1 Image corrupt or truncated. player.png Loading failed for the <script> with source “https://bat.bing.com/bat.js”. staffpicks:1 Loading failed for the <script> with source “https://googleads.g.doubleclick.net/pagead/viewthroughconversion/993702637/?random=1530200067190&cv=9&fst=1530200067190&num=1&guid=ON&resp=GooglemKTybQhCsO&u_h=768&u_w=1366&u_ah=728&u_aw=1366&u_cd=24&u_his=1&u_tz=-180&u_java=false&u_nplug=1&u_nmime=2&gtm=G6c&sendb=1&frm=0&url=https%3A%2F%2Fvimeo.com%2Fchannels%2Fstaffpicks&ref=https%3A%2F%2Fvimeo.com%2Fpt-br&tiba=Vimeo%20Staff%20Picks%20on%20Vimeo&async=1&rfmt=3&fmt=4”. staffpicks:1 Cannot play media. No decoders for requested formats: video/mp4; codecs="hvc1", video/mp4; codecs="hvc1" Consegui solucionar o problema alterando essa configuração: media.gpu-process-decoder > false PC: Windows 7 x64 @ AMD E-350