Demo Page working but can't get my own code to work.

If I open my app and then go to https://median.dev/library-ready/ it seems to work fine. But If I add this to my start page it does nothing.

// Set screen brightness and statusbar styling as soon as page loads
function median_library_ready(){
// Set screen brightness to 80%
median.screen.setBrightness(0.8);

// Set status bar to light mode, red color, with overlay
median.statusbar.set({
'style':'light',
'color':'80ff0000',
'overlay':true
});
}

This is just copied off of the example pages so I figured it would work.