MutationObserverInit.childList

The MutationObserverInit dictionary's optional childList property indicates whether or not to monitor the specified node or nodes for the addition or removal of new child nodes.

If childList is false (the default), adding or removing new nodes does not trigger mutation callbacks. By setting childList to true, your callback will be invoked any time nodes are added to or removed from the DOM node or nodes being watched.

A Boolean value indicating whether or not to invoke the callback function when new nodes are added to or removed from the section of the DOM being monitored.. If subtree is false, only the node indicated by the observer's target node is monitored for changes. Setting subtree to true causes addition or removal of nodes anywhere within the subtree rooted at target to be reported.