Pedal Markings Should Go at Bottom of Grand Staff
I couldn't decide if this was a duplicate of #15513: Pedal markings under grand staff can only be attached to notes in staff attached to. Since that issue is 2 years old, I thought I'd start with a new issue.
If, in a grand staff, notes appear only in the upper staff, it is not possible to add pedal markings using the lower staff that are less than an entire measure in length. In #15513: Pedal markings under grand staff can only be attached to notes in staff attached to, the workaround was to create invisible notes in the lower staff so that the pedal markings could be properly attached. In my attached example, the pedal markings were anchored to notes in the upper staff. The pedal marks can then be manually adjusted to match the position of the lower staff pedal marks.
A better solution would be to always place the pedal marks at the bottom of the grand staff (and sometimes the grand staff has more than 2 staves). The best solution would allow the start and end of the pedal marks to be aligned with any notes in any of the grand staff staves. It is possible for a pedal marking to need a starting anchor in one staff and an ending anchor in another (it's probably rare). This could be done in the same way that cross-staff slurs are created.
I consider the current behavior to be a bug that can be worked around. This is not a feature requests—MuseScore supports pedal markings, but not correctly.