Soundfont Midi Player might be a bit more popular than UltraStar WorldParty. We know about 1 link to it since March 2021 and only 1 link to UltraStar WorldParty. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Anyway, this site (https://ultrastar-es.org/en) is probably your best bet for the app and music. Source: about 2 years ago
For Windows, I find "Soundfont Midi Player" https://falcosoft.hu/softwares.html#midiplayer to be the best choice. It uses a Bassmidi based player with a provided soundfont, and MIDI files sound great on it. I have not tested it on Wine. - Source: Hacker News / 5 months ago
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