Create notes and highlight bars

A lot of times when im composing a piece, i will write a tentative bars here and there which i intend to revise later. which is why i think it will be cool for us to have the ability to highlight a bar for a color of your choice (to mark the bars that you want to change), in addition to that, a "+" sign that shows up when hovering over the highlighted bar so that you can write notes (notes regarding ideas, changes whatever).

I think the combination of highlighting bars and adding hidden notes would help people in their composition workflow.