Issues with the rest entry button
Issue 1: If the rest entry button is selected, then another note length is selected or keyboard-shortcutted, the rest gets unselected. This makes inputting rests by mouse quite difficult as it requires the rest button to be clicked every time the note length changes. This is especially time-consuming when using the keyboard to change note lengths.
Issue 2: If the rest entry button is selected, the keyboard shortcuts for inputting specific notes input rests. ‘0’ is already a shortcut for rests, so the other keys producing rests isn't necessary. As a use case, if I want to put in a phrase that starts with a rest, I'd want to click the note value, click the rest entry button, click on the location I want that rest to be, and then type the rest of the phrase by keyboard.
I don't know if changes to this would break any workflows. But at the moment, if I want to input a rest somewhere that requires mouse intervention, I click the note in, press delete, press N to leave note entry mode, and enter the correct duration.