toggle Slack channels list

slack.js

var channels = document.querySelector('.channel_list_header_label');
var list = document.querySelector('#channel-list');
channels.addEventListener('click', function(e){
e.preventDefault();e.stopImmediatePropagation();

if (list.style.height != '20px') {
list.style.height = '20px';list.style.overflowY = 'scroll';
} else {
list.style.height = 'auto';list.style.overflowY = 'auto';
}
});