This is a very hacky solution to copy Liked songs to a playlist since YTM still doesn't have the functionality. I'm using this to copy songs out of YTM to another service, then unsubscribing. Thus, I won't be maintaining it (or ever using it again). It will only work while the YTM interface is the same as it is today (3/6/21) and will break once they make updates.
Steps to use:
- Create a new playlist
- Go to your Likes page (in chrome, on a desktop or laptop). Scroll to the bottom so all songs are loaded
- Open Chrome's dev tools (F12 on windows), go to the console
- Paste the script below. Edit the first line, replace "YOUR_PLAYLIST_NAME" with your playlist's name
- Press enter