I haven't tested yet on YouTube, but I have noticed that InstaGram seems to have found a way to block my downloads. Nothing will download now.
I too have been enjoying VideoDownloadHelper extensively, and hate to see those two most important sites go; YouTube and Instagram.
I also wanted to mention that I have been looking up my listings on those two sites with my favorite browser, Chrome (Windows 10 64-Bit) and then I copy the links and take them over to FireSlop (I like it, but I love playing word games. What I really mean is FireFox, which is an excellent Browser, I just prefer Chrome) and then, as had been mentioned somewhere back there in some documentation I read, FireFox was much better at grabbing the .MP4 Downloads from those two sites (YouTube and Instagram).
I am sure that the Techs are on this situation like "white on rice" (a correct expression for most Americans who eat mainly white rice) in other words, the Techs are going to be slamming this with everything they've got. They've got a VERY GOOD THING going here with VideoDownloadHelper and are probably making money hand-over-fist, (as the expression goes) and no doubt wish to keep the money flowing. So my suggestion is, "Stand fast, be patient, and I'm certain a solution shall be along shortly."
I still Love the quote of Jewels in Pulp Fiction in the short story "The Bonnie Situation" where he tells Marsella Wallace, "I don't want to hear no stories Marsellas. The words I wanna here are, "no problem, Jewels. go and chill those guys out, Jewels, and Wait for the Cavalry which will be showing up promptly, Jewels!" - a movie you and I and all of us can watch on our own while we wait for the Cavalry (Techs) coming over the Hill so we can get back to archiving interesting content.
Sol