Group Instruments Into the same staff if there are more than one a part.
Let's say there are 2 Alto Sax parts in a piece of music. In MuseScore, you can see both Alto parts on different staffs. But there should be a "Part Grouping" feature where you can combine those two Alto parts (or any other instrument with 2 or more parts) into one staff. Then there should be 2 buttons by the staff with A. Sax. 1 and A. Sax. 2. When you click the button by A. Sax. 1, it will enable you to add notes & edit just A. Sax. 1, also maybe when clicked, all the other parts (in the staff with that grouped instrument) notes fade slightly so you know exactly what notes belong to A. Sax. 1, or whatever part is being edited. This is used in real pieces of music to not clutter the page and take up too much space. This would greatly help with page space, because all the parts I'm using are taking the whole page and even falling off the page to where it's not visible or editable. Thank you, and please take this into consideration.
Comments
Two parts on one stave is an abomination! It is invariably difficult to read. One of my most frequent uses of Musescore is creating separate 1st and 2nd parts from shared parts.
If you really must do it then you can use the implode function after creating the individual parts. See https://musescore.org/en/handbook/4/implode-and-explode
But much better...don't.
It is already possible to combine parts onto a single staff for the score but work with and print them separately as parts. See the Handbook section on Parts in the Basics chapter for more info. Additional controls for even more flexibility in the future are currently being designed.