Important! – Symbols, staves, and voices
Most symbols belong to a staff when inserted. Only note symbols, slurs and ties are an exception. They belong to notes and therefore to voices.
It is extremely important that the correct staff is active when you insert a symbol (if you are editing multiple staves).
If you for example insert a symbol while the wrong staff is active, the symbol might later “disappear” because you edit another configuration of tracks (the track you actually inserted the symbol on might not be opened for editing).
The same is true for note symbols and their relation to voices. Make sure that the correct voice is active when inserting symbols or they might wind up at the wrong position, fermatas may be turned upside down, etc.
Layout symbols work slightly differently. Instead of belonging to a certain staff or voice, they belong to a layout. Since different track combinations use different layouts, this means that if you insert a layout symbol in the score when you are editing two tracks (for example a trumpet and a saxophone part), it is not there when you view each track by itself in the Score Editor. If you want the same symbols to appear in other layouts as well, you can copy the form of one layout to another. If you want a symbol to appear in all layouts, use the Project layer.