I tried saving YouTube video for later viewing through download but it turns out the feature is somewhat broken. I ended up losing track of the videos I had stored in my account. (I am still not sure how it happened )

How do you guys keep track of your videos? Is there a tool that can help me save all the design videos in a wallet sort of thing? I don't trust browser bookmarks and YouTube failed me recently with the saved videos. So, I am looking for options other than those two.