'Regroup rhythms' removes slurs when shorter rests or notes appear in another voice

[futamapapa]

Issue type

Engraving bug (incorrect score rendering)

Description with steps to reproduce

1. Create a new score.
2. In voice 1, place two 1/4 notes connected by a slur at the beginning.
3. In voice 2, place an 1/8 rest (or note) at the beginning.
4. Apply 'Tool/Regroup rhythms' to the score.

Expected behavior: The slur remains.
Actual behavior: The slur disappears.

Supporting files, videos and screenshots

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

MuseScore Studio version (64-bit): 4.5.0-250540404, revision: github-musescore-musescore-ca58934

Regression

Yes, this used to work in a previous version of MuseScore 4.x

Operating system

OS: Windows 10 Version 2009 or later, Arch.: x86_64

Additional context

This issue occurs only when a rest/note in another voice is shorter than and coincides with the penultimate note under the slur.
It does not occur in versions 3.6.2, 3.7.0 (Nightly), or 4.4.0.
The issue has been present since version 4.4.1.

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