Crash on adding courtesy accidentals (Windows only)

Issue type

Crash or freeze

Description with steps to reproduce

1. Enable the Courtesy Accidentals plugin
2. Open the attached score (MSS 4.4.4 courtesy accidentals crash.zip)
3. Run Configure Courtesy Accidentals, select 'Notes up to the next 2 measures' option
4. Click 'Add accidentals'... crash!

See https://github.com/musescore/MuseScore/issues/25975#issuecomment-2590715901 for details

Supporting files, videos and screenshots

MSS 4.4.4 courtesy accidentals crash.zip

What is the latest version of MuseScore Studio where this issue is present?

4.4.4-243461245, revision: github-musescore-musescore-2232670

Regression

Yes, this used to work in MuseScore 4.4.2

The crash started to happen in 4.4.3 (when we migrated to Qt 6.2.9 on Windows)

Operating system

Windows 11 Version 2009 or later, Arch.: x86_64

Additional context

I've reinstalled MSS, deleted the plugins from my user Documents folder, and tried on another machine and in every case, while I can use the Add command to get bare accidentals, using the Configure window always causes a crash.

I've tried to reproduce this with a blank new score for a minimal test case, but it seems to work fine with just two notes in the score!

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