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i also see 1080p without audio option in more section. what we need is to see 1080p or 4K (whatever size uploaded) next to green download button instead of maximum 720p. 
It is showing maximum 720p quality on all youtube videos and never 1080p or 4K.

Browser: Safari 8.0 Mac OS X User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/600.1.25 (KHTML, like Gecko) Version/8.0 Safari/600.1.25 Extension: safari 4.40
why it is not showing 1080p or 4K download option though video has 1080p version on youtube ?