# Page Not Found

The URL `appendix/upgrade-from-musescore-3x` does not exist.

You might be looking for one of these pages:
- [Upgrade from MuseScore 3.x](https://handbook.musescore.org/pl/appendix/upgrade-from-musescore-3.x.md)
- [Command line usage](https://handbook.musescore.org/pl/appendix/command-line-usage.md)
- [Changes for MDL percussion](https://handbook.musescore.org/pl/appendix/changes-for-mdl-percussion.md)
- [Słowniczek](https://handbook.musescore.org/pl/appendix/glossary.md)
- [Music fonts](https://handbook.musescore.org/pl/appendix/music-fonts.md)

## How to find the correct page

1. **Browse the full index**: [/sitemap.md](https://handbook.musescore.org/sitemap.md) - Complete documentation index
2. **View the full content**: [/llms-full.txt](https://handbook.musescore.org/llms-full.txt) - Full content export

## Tips for requesting documentation

- For markdown responses, append `.md` to URLs (e.g., `/pl/appendix/upgrade-from-musescore-3.x.md`)
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