Ultrastar Deluxe Rap Edition
Ultrastar Deluxe didn't have any support for rap notes until around the end of 2016, beginning of 2017, and its use isn't even really that well known in general. And, since the official stable release doesn't have the rap note support, I'll be sharing my build.
Note that I'll only be sharing the executable, since the entire package would be about 50 MB. So, before you could use it, you could just download a pre-built package, then overwrite the executable with this version.
Note that if you download a build that's recent, chances are it already has rap notes. If it doesn't, you could always just build it yourself if you really want to be sure you have the latest version.
Download (2 MB, 2 times downloaded)
GitHub repository: https://github.com/UltraStar-Deluxe/USDX