A minor change in the UA string override we send for m.youtube.com does the trick: the "Chromium" token needs to be changed to "Chrome". I.e. the new override rule becomes:
[/^https?:\/\/m\.youtube\.com\//, "Mozilla/5.0 (Linux; Ubuntu 14.04 like Android 4.4;) AppleWebKit/537.36 Chrome/35.0.1870.2 Mobile Safari/537.36"]
A minor change in the UA string override we send for m.youtube.com does the trick: the "Chromium" token needs to be changed to "Chrome". I.e. the new override rule becomes:
[/^ https?: \/\/m\. youtube\ .com\// , "Mozilla/5.0 (Linux; Ubuntu 14.04 like Android 4.4;) AppleWebKit/537.36 Chrome/35.0.1870.2 Mobile Safari/537.36"]