Two staves, one hidden—barline shown at beginning of each line
This is an enormously esoteric issue, but screenshots will help me to describe it.
Normally, at the beginning of each line, the barline is not not shown, as in this screenshot—look closely at it and make sure you see what I'm talking about:
Naturally, though, if you're dealing with (say) a piano part, where there are two staves which are connected, the beginning of the line looks like this:
Then comes the bug. If one of those staves is empty, and you have "Hide empty staves" selected in the Style pane, then you should have a normal-looking single staff. But you don't. It looks like this:
Do you see it? Look back at the first screenshot and see the difference. The worst thing about this is that there seems to be no workaround.
I really, really hope this is considered significant enough to be fixed.