[MU4 Issue] Spanners (hairpins, voltas, lines...) are reportedly sometimes missing in part scores

[cbjeukendrup]

Describe the bug
On musescore.org, there have been a few reports where spanners don't show up in part scores. It is not yet clear what causes this.

• https://musescore.org/en/node/341765
• https://musescore.org/en/node/342954
• https://musescore.org/en/node/343502
• https://musescore.org/en/node/343620

[cbjeukendrup]

Throwing this into 4.0.2 for now, but if we don't find out soon enough how to reproduce it, I don't think we should consider it a blocker. It seems not that common and there is an easy workaround of copy-pasting.

[oktophonie]

I've noticed slurs from grace notes occasionally disappearing, too.

[MarcSabatella]

Supposedly https://musescore.org/en/node/342954#comment-1170167 and the comment following have steps to reproduce.

[AntoniSchonken]

Is there a best practice way to log and output keystrokes/actions in MS? This problem is affecting me consistently, and I would like to produce proper/useful logs to help identify its source (if possible).

[bmarwell]

Throwing in: It never has happend to me when opening a single part. But sometimes on large scores when:

1. opening a few single parts
2. Then opening all other parts at once.

• Re-adding voltas to one of the new parts sometimes causes the first few (previously opened) parts to have two same voltas in the same bar.
• Playback and score is unaffacted
• The parts menu now shows scores which shouldn't be there (e.g. their names is just '3' or so).

Maybe this helps in reproducing the issue. I can give you a score where this has happened, but cannot be public.

[Jojo-Schmitz]

Also reported in https://musescore.org/en/node/345824

[mike-spa]

I'm sorry, everyone, but this is not a workable issue. Before I (or anyone else) can even try to find the cause, there has to be a reliable way of reproducing it.

Attaching files showing the missing spanners in parts is of no help in this case, because the parts have already been created and (typically) extensively worked on, so it's impossible to back track what happened. And invariably, with all of these files, if I reset the corrupted part, or simply create a new part with the same instrument, everything is displayed correctly, which means that the creation of parts works propertly and, again, we can't know where the problem is. [Also, as a side note: please advise users to regenerate the part, if they find themselves in these situations, and if they can do so without loosing too much work].

We know it's a serious issue that keeps being reported, but please help us out. Anectodal evidence isn't helpful. Hundreds of random unrelated steps even less so. If anyone manages to nail this down to a clear, repeatable set of operations, I'm sure we'll figure it out quickly.

[bmarwell]

FWIW, I will try to create a Minimal, reproducible example soon.

[bkunda]

Closing this for now as it hasn't had any activity for 3 weeks and still seems to not be reproducible.
Happy to re-open this if it can be reliably reproduced.