Edit handles for tie appear above wrong staff

I guess it's by using cross-staff notation. If so, confirmed.

Steps:

1) Grand staff template
2) In treble staff, enter two quarter notes C4 (tied) + C + D (with slur)
3) Select the measure -> press Ctrl + Shift + Down arrow - for cross-staff notation

Result: tie and slur are disconnected to the notes (and remain above the treble staff)

After a first check, this issue has always been there (in the 3.0 dev.)

This seems to be another form of #279182: Cross-staff slurs/ties trying to avoid note on wrong staff.

It's exactly that.

No cross staff notation here.

I forgot to make it active.

Indeed, and I suspect the original issue was no about cross-staff either. As far I can tell, everything works fine but it's indeed difficult to edit the tie. And to be clear: the issue is only ties, not slurs, or else this would be P0 to me (it's borderline as is).

I used a tie that allowed you to see both the tie and the edit handles. In the score the picture was taken from I first tried it with the contrabass, but it was impossible to see both the tie and the handles at the same time.

True. I checked and you can still scroll or zoom and things do work, plus editing of ties is not as common as editing of slurs. Still, I'll check to see if it's an easy fix...

See https://github.com/musescore/MuseScore/pull/4567

Fixed in branch master, commit 007a74e9af

fix #280383: bad edit handles for ties

Fixed in branch master, commit 6f14bc17f1

Merge pull request #4567 from MarcSabatella/280383-tie-handles

fix #280383: bad edit handles for ties

Fixed in branch 3.0.1, commit a933e5a321

Merge pull request #4567 from MarcSabatella/280383-tie-handles

fix #280383: bad edit handles for ties

Automatically closed -- issue fixed for 2 weeks with no activity.