Hide when empty: Instrument does not work (acts same as Auto)
The new Instrument setting for "Hide when empty" in Staff Properties is not doing what it was designed to do. The idea was that when using Hide empty staves, you might want have the whole grand staff either present or not, rather than having the top staff of the piano part hidden but the bottom not. This isn't working - the top staff does get hidden if empty and "Hide empty staves" is enabled. For instance:
1) load attached file
2) Format / Style
3) Enable Hide empty staves
Result: top staff of piano disappears on second system even though bottom staff is still present (as it should be). Both staves of the piano part have been set to "Instrument" under "Hide when empty".