You edit button symbols in the Button Editor. The instance properties that you can modify are those that are typically consistent among buttons in a nav bar:
Modifications to graphical appearance such as stroke color and type, fill color and type, path shape, and images
Live Filters or opacity applied to individual objects in the button symbol
Size and position of the active area
Core button behavior
Optimization and export settings
URL link (also available as an instance-level property)
Target frame (also available as an instance-level property)
To edit button properties at the symbol level:
Do one of the following to open the button in the Button Editor:
Double-click a button instance in the workspace.
In the Library panel, double-click the button preview or the symbol icon beside the button symbol.
Make changes to the button's characteristics, and click Done.
Changes are applied to all instances of the button symbol.