Extra rest inserted when parsing MusicXML with backup/forward tags

[werneta]

music21 version

9.1.0

Problem summary
I'm working in MuseScore 4 and have a 4/4 measure with a double-dotted half note, followed by a clef change, followed by an eighth note:

When I convert this to MusicXML and import it with music21, there is an extra rest inserted after the clef change. It looks like it's related to <backup> and <forward> tags that are MuseScore adds around the clef change.

Steps to reproduce
Use this file (remove the .txt) from the file name:
clef_change_backup.musicxml.txt

import music21
fname = 'clef_change_backup.musicxml'
x = music21.converter.parseFile(fname)
list(x[1][1])

Expected vs. actual behavior

[<music21.clef.TrebleClef>,
 <music21.key.KeySignature of no sharps or flats>,
 <music21.meter.TimeSignature 4/4>,
 <music21.note.Note C>,
 <music21.clef.BassClef>,
 <music21.note.Rest dotted-quarter>, # Not expected
 <music21.note.Note C>,
 <music21.bar.Barline type=final>]

More information

I tried removing the <backup> and <forward> tags in the XML:

      <note>
        <pitch>
          <step>C</step>
          <octave>5</octave>
          </pitch>
        <duration>7</duration>
        <voice>1</voice>
        <type>half</type>
        <dot/>
        <dot/>
        <stem>down</stem>
        </note>
      <backup> <!-- Removed this element -->
        <duration>3</duration>
        </backup>
      <attributes>
        <clef>
          <sign>F</sign>
          <line>4</line>
          </clef>
        </attributes>
      <forward> <!-- Removed this element -->
        <duration>3</duration>
        </forward>
      <note>
        <pitch>
          <step>C</step>
          <octave>3</octave>
          </pitch>
        <duration>1</duration>
        <voice>1</voice>
        <type>eighth</type>
        <stem>up</stem>
        </note>

and saved it as this file: clef_change_nobackup.musicxml.txt

Rerunning the previous steps generates the expected output:

[<music21.clef.TrebleClef>,
 <music21.key.KeySignature of no sharps or flats>,
 <music21.meter.TimeSignature 4/4>,
 <music21.note.Note C>,
 <music21.clef.BassClef>,
 <music21.note.Note C>,
 <music21.bar.Barline type=final>]

[jacobtylerwalls]

Hi, this should be fixed after #1777, please reopen if not!