Debouncing issues with setWatch();

Firmware 1v79

I have a noisy button on B5.

The default debounce setting (10ms) per setWatch() docs doesn't seem to do anything. When I add debounce: 20 (or any value), it prevents the callback from getting any args. Code below.

Recommendations?

var button=B5;
pinMode(button, 'input_pulldown');
function buttonPressed(info) {
        console.log(info);  // [ undefined ]
        info.time;   // Uncaught Error: Field or method "time" does not already exist, and can't create it on undefined
}
setWatch(buttonPressed,button,
         {repeat:true,debounce:200});