When viewing an activity on Garmin Connect, the map has a fixed height. Especially on larger screens, you may want to view a larger map, but there is no built-in option to resize the map.
Using this bookmarklet, you can view the map in the full browser window.
You may have to zoom in and out (Ctrl+, Ctrl-) to trigger the map to adapt to the new size.
The bookmarklet runs this JavaScript code:
javascript:(function(){
var e = document.getElementById('activity-map-canvas');
if (!e) {
alert('No map element found');
return;
}
if (e.style.position === 'relative') {
e.style.position = 'fixed';
e.style.top = 0;
e.style.left = 0;
e.style.right = 0;
e.style.height ='100%';
e.style.zIndex = 100;
} else {
e.style.height='400px';
e.style.position = 'relative'
}
})();