Crash on creating a score

[shoogle]

Issue type

Crash or freeze

Description with steps to reproduce

1. Launch app.
2. New Score dialog > Add flute > Done.

The score appears for 1 second and then the app crashes.

Supporting files, videos and screenshots

The app also crashed when I saved this diagnostics file, but hopefully it's complete:

• Windows_diagnostics.zip

In which versions of MuseScore Studio is this issue present?

Latest nightly master (build 260324034, commit fe93b24)

Regression

Yes, this works in the latest released version and is broken in the nightly builds

Operating system

Windows 11, macOS 26

Additional context

Crash still occurs on Windows and macOS even in builds of these PRs:

• added ioc context for QWidgets dialogs #32757
• fixed EditMidiMappingModel destruction #32760

On Linux the crash no longer occurs after those PRs.

Checklist

• This report follows the guidelines for reporting bugs and issues
• I have verified that this issue has not been logged before, by searching the issue tracker for similar issues
• I have attached all requested files and information to this report
• I have attempted to identify the root problem as concisely as possible, and have used minimal reproducible examples where possible

[shoogle]

@DmitryArefiev, the crash still happens for me in your recent "Build: All" run even after a factory reset (-F).

Sometimes it takes a few minutes to crash on macOS, but normally it happens as soon as I click 'Done' in the New Score dialog.

[DmitryArefiev]

@shoogle Hm.. I can't get a crash in 5.0.0.260324122 on macOS 13.7.8

Screen.Recording.2026-03-24.at.18.46.22.mp4