I’m trying (and failing) to figure out how Safari manages to get command-= to increase the font size, when it’s menu’s key equivalent looks like it’s hooked up to command-+

Basically, I’m trying to figure out to not require my users to have to use the shift key when they want to increase the font size. One idea I had was to create a hidden menu with command-= set to call my action, but unfortunately people found it anyway. Has anyone got any suggestions for me?