Measure repeats on parts not expanding on MIDI export

Issue type

Import/export issue

Description with steps to reproduce

1. Go to a part with measure repeats (not repeated sections in repeat bars), in Mixer mute every other part.
2. Choose File -> Export, select the part check box only, and choose MIDI, with "Expand Repeats" on.
3. Save file. Output MIDI file has empty measure where MIDI notes should be as part of the measure repeat.
4. Go to the score.
5. Choose File -> Export, select the score check box only, and choose MIDI, with "Expand Repeats" on.
6. The part used in items 1-3 now has all measures populated in the MIDI file where the measure repeats are.

The measure repeats should be expanded whether you export just the single part or you export the whole score and get the part in question. However, measure repeat expansion only occurs when the whole score is exported.

Supporting files, videos and screenshots

I have attached the Musescore score, the MIDI file containing the export of the whole score, and the MIDI file generated when just exporting one part (Drums).

MeasureRepeatProblem.zip

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

OS: macOS 15.3, Arch.: arm64, MuseScore Studio version (64-bit): 4.5.1-250800846, revision: github-musescore-musescore-603eca8

Regression

I was unable to check

Operating system

MacOS 15.3.2

Additional context

No response

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