I am trying to flatten an array of objects of arrays. For example, we might have something like so:

```
[{ numbers: [1, 2, 3] }, { numbers: [4, 5] }, { numbers: [6] }]

```

I would like to flatten it into:

```
[1, 2, 3, 4, 5, 6]

```

I have a working solution doing something like this:

```js
const arr = [{ numbers: [1, 2, 3] }, { numbers: [4, 5] }, { numbers: [6] }];
const almostFlattened = arr.map((obj) => obj.numbers);
const flattened = [].concat.apply([], almostFlattened);
console.log(flattened);
```

Does anyone know of an easier or more performant solution here, preferably without the `almostFlattened` middle step?