Support for 4320p60 / 8K

[FireMasterK]

title, The adaptive stream is as follows:

{
"itag":272,
"url":"https://r5---sn-npoe7ner.googlevideo.com/videoplayback?expire=1608236718&ei=TmrbX_StM8364-EP2aiVyAY&ip=94.198.43.77&id=o-AFxDb1xUEfU_bkofMhgL0SaNnUGf60hQvJlnMu5viQFM&itag=272&aitags=133%2C134%2C135%2C136%2C160%2C242%2C243%2C244%2C247%2C272%2C278%2C298%2C299%2C302%2C303%2C308%2C315%2C330%2C331%2C332%2C333%2C334%2C335%2C336%2C337%2C394%2C395%2C396%2C397%2C398%2C399&source=youtube&requiressl=yes&mh=XR&mm=31%2C26&mn=sn-npoe7ner%2Csn-i3belnlz&ms=au%2Conr&mv=m&mvi=5&pl=24&initcwndbps=321250&vprv=1&mime=video%2Fwebm&ns=Fqk8atfteNvT4Q1N_6mo5msF&gir=yes&clen=849820003&dur=268.966&lmt=1576096789562597&mt=1608214613&fvip=5&keepalive=yes&c=WEB&txp=5311222&n=9HlmABm6R8Kg_Z6mj&sparams=expire%2Cei%2Cip%2Cid%2Caitags%2Csource%2Crequiressl%2Cvprv%2Cmime%2Cns%2Cgir%2Cclen%2Cdur%2Clmt&sig=AOq0QJ8wRQIgWbVaNbH-ku1MLBnKpYzXc0M7B9YV7VXGtgmhpcBNEcQCIQDYY2uCaOVhdfm42fhjXEYQCqXxgSgEmFw_BfUrZYNnVA%3D%3D&lsparams=mh%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AG3C_xAwRQIgUG6ap635XRkXNE7hStW_yOWeeJcdcz4DW6M2CTcHUr8CIQCy-hLeQgk6qLCQKUzaJhs6BTg3fRc2F6WKcbUrh46rMQ%3D%3D",
"mimeType":"video/webm; codecs="vp9"",
"bitrate":43338259,
"width":7680,
"height":4320,
"initRange":{
"start":"0",
"end":"219"
},
"indexRange":{
"start":"220",
"end":"1162"
},
"lastModified":"1576096789562597",
"contentLength":"849820003",
"quality":"highres",
"fps":60,
"qualityLabel":"4320p60",
"projectionType":"RECTANGULAR",
"averageBitrate":25276652,
"colorInfo":{
"primaries":"COLOR_PRIMARIES_BT709",
"transferCharacteristics":"COLOR_TRANSFER_CHARACTERISTICS_BT709",
"matrixCoefficients":"COLOR_MATRIX_COEFFICIENTS_BT709"
},
"approxDurationMs":"268966"
}

Example URL: https://www.youtube.com/watch?v=RGoPU-OLQHE

Something to note is that 8K videos that are 60fps do not have a 30fps variant.