Unexpected space increases between staves when applying second voice icon, non-reversable

[mskutsch]

Issue type

UX/Interaction bug (incorrect behaviour)

Description with steps to reproduce

1. When converting a two-note chord with single up-stem to two voices (with one up-, one down- stem), using the 1st and 2nd voice icon
2. Sometimes, but not always, this causes the stave below to move down one step, increasing distance beween staves unnecessarily, Changing the next chord in similar way causes stave below to move down one more step, etc. so that first two, and eventually only one (4-stave) system fits on each page (rather than 3 systems fitting nicely).
3. This cannot be reversed by using the un-do icon; if you do this, the stave below just moves even further down.
4. This can be seen in attached screenshots. On first page the operation has been successful, many chords have been split into two voices, but the problem starts if you try doing this in first bar of second page.
5. Screenshot 1 shows correct behaviour on page 1, and up-stem for the chords in Bar 18, page 2. Screenshot 2 shows what happens when the lower notes are is given a down-stem in Bar 18, and please note the gap between staves, which only increases as more notes are treated with down-stems

Supporting files, videos and screenshots

(screenshot 1)

(screenshot 2)

(screenshot 3)

In which versions of MuseScore Studio is this issue present?

4.6.5

Regression

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

Operating system

Windows 11

Additional context

I first checked in the Forum and was advised that this must be a bug and should be reported (HildeK)

I hope you can access the screenshots from the link pasted above. I would have preferred to send the Musescore file itself but your system evidently cannot read 4.6.5 yet, at least it could only identify files from earlier versions, on my computer.

My email contact is mskutsch@ciga.unam.mx if needed for contact.

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

[MarcSabatella]

To attach a score or any other file format that GitHub doesn't recognize, just ZIP it. Then be sure to give precise steps to reproduce the problem - say which specific note or notes you are selecting, and which commands you are doing from that point forward.

Most likely your page is full and just barely on the edge of not being able to fit as many systems as it currently does, and the voice change results in a stem change and/or other small changes that are just enough to put it over the edge. And once MuseScore decides it cannot fit as many systems, it spreads the remaining staves out to fill the page. That much is normal. But undo should put it back and does normally. Could well be you are encountering some corner case where it doesn't, but that's why a specific score and precise steps would be useful

[MarcSabatella]

Scratch that, I see your forum post now with the score and @jeetee's steps, and can reproduce the problem as well.

For the record, see https://musescore.org/en/node/389827 for the for the score. To reproduce the problem, select the B in the soprano staff in bar 8 and move it to voice 2.

Turning on the engraving diagnostics in a nightly build of 4.7, I have a pretty good idea of what is happening. Moving the B to voice 2 is also moving the lyric "?" to voice 2 (which it probably shouldn't, since the E remains), but the hyphen that previously connected it to the previous lyric "who" is not being cleaned up. So now you have the lyric "who" in voice 1 bar 17 ghost-hyphenated to the lyric "?" in voice 2 in bar 18. The ghost hyphen keeps moving lower and lower with each edit. I am guessing it keeps trying to avoid itself in the skyline.

You can reproduce this easily from scratch by entering two notes in voice 1, adding the lyric "ly-ric" or anything else hyphenated, then moving the second note to voice 2. The hyphen disappears but is still in the skyline, and it moves lower with each edit and eventually pushes the next staff/system down.

[mskutsch]

Thank you so much, I am so grateful you can see what the problem is. I will have a go and let you know if it works.