This was obviously already here, but someone should remove the `bind(this)` from these `.forEach` callbacks and just use the built-in `thisArg`:

```js
// Change this:
pickerElements.forEach((function pickerElements_forEach(className) {
  var element = document.querySelector(className);
  element.addEventListener('mousedown', this);
}).bind(this));


// To this:
pickerElements.forEach(function(className) {
  context.querySelector(className).addEventListener('mousedown', this);
}, this);
```

Using the `thisArg` avoids the creation of another function in memory.