@Hugo - a valid feature request that we would love to offer out of the box, it has been blocked for some time, unfortunately. Please follow along/vote on this existing request here that we’re tracking: Update Multiple Records at once
Our dev docs cover adding the checkboxes by the way (JavaScript & jQuery Examples), but does not include any action, which is what @JonathanTack has appended with. Thanks for sharing your code, Jonathan! Hope a custom solution can help in the meantime.