Crippleware that forces you to install "helper app" that (unnecessarily) downloads the video/audio streams separately, all on the PRETEXT of "merging" of streams - when it actually NEEDLESSLY re-encodes the entire video, just to inject a watermark that you have to "pay" to remove - all while wasting time (up 1000x compared to just straightforward "muxing" of combining the video and audio file) and DEGRADING video quality. Furthermore, the "companion app" needlessly attempts to install as a "privileged" application on Windows, claiming it is needed to "help download streams"... Stay away and just use DownloadThemAll! (which disproves this "need") and uses the browser engine (i.e. keeping all browser headers, cookies and referrer inside the browser), instead of leaking it all to the "companion app" just to do the same downloading action (and of course, the totally unneeded forced quality-degrading, time-wasting, watermark-adding "processing").