We have been moaning about the lack of innovation in advertising for some years, in an industry stagnated by formats and stifled by privacy concerns. Arguably the most disruptive consumer-facing product launch of recent years in the advertising realm has been the divisive Free Telly, with its dedicated second screen for ads – although even this is seen by many as an experimental gimmick rather than a serious trendsetter. Enter Roku – which is planning to throw a contentious curveball at the conventions of TV advertising. The US streaming company has submitted a patent application to hijack HDMI feeds connecting Roku’s proprietary TV sets with external streaming devices – providing the increasingly ad-reliant Roku with a very novel (and very…