bad bend retention in 4.3.2 and 4.4 nightly

Issue type

General playback bug

Description with steps to reproduce

If a file is generated in 3.6.2 or 3.7 Evo, all guitar bends have no playback effect in 4.3.2 or 4.4 nightly.

Back during 3.6 and 3.7, all six of the guitar bends only required one note - no target note.
When you open a 3.x file in 4.3 or 4.4 nightly, all of these bends do nothing on playback.
The curve graph is there, but with no line and nothing to edit.
If I'm not mistaken, 4.3 and 4.4 still have the 'slight bend', which behaves similarly.
It seems to me all of the old bends could possibly be imported as slight bends with their curves kept intact or nearly so.

Supporting files, videos and screenshots

bend retention failure.zip

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

OS: Windows 10 Version 2009 or later, Arch.: x86_64, MuseScore Studio version (64-bit): 4.4.0-242160304, revision: github-musescore-musescore-cc49f21

Regression

Yes, this used to work in MuseScore 3.x and now is broken

Operating system

Windows 10 64 home

Additional context

Also does not work in OS: Windows 10 Version 2009 or later, Arch.: x86_64, MuseScore Studio version (64-bit): 4.3.2-241630831, revision: github-musescore-musescore-22b46f2

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

Start by opening bend retention failure.zip in MuseScore Studio 4.4.0 and comparing playback with MuseScore 3.6.2 or 3.7 Evo. Trace how the older one-note guitar bends are imported and played back; done means the bends produce playback effects and their curves remain available for editing.