https://www.girong.com/youtube-click-to-enable-video-converter/

Created by Surf Island Solutions, Video Converter is a potentially unwanted program (PUP) that claims to enable conversion of video formats and to solve all video-related problems. On initial inspection, this functionality may seem legitimate and useful, however, be aware that Video Converter is considered to be adware, since it employs a deceptive software marketing method called ‘bundling’ (stealth installation of additional programs together with the chosen software) to install on Internet browsers (Internet Explorer, Google Chrome, and Mozilla Firefox) without users’ consent.