code: function handlePostLockTakeover( calypsoPort ) {
  	const unsubscribe = subscribe( () => {
  		const isLocked = select( 'core/editor' ).isPostLocked();
  		const isLockTakeover = select( 'core/editor' ).isPostLockTakeover();
  		const allPostsButton = document.querySelector( 'div.editor-post-locked-modal__buttons > a' );
  
  		const isPostTakeoverDialog = isLocked && isLockTakeover && allPostsButton;
  
  		if ( isPostTakeoverDialog ) {
  			//handle All Posts button click event
  			allPostsButton.addEventListener(
  				'click',
  				event => {
  					event.preventDefault();
  					calypsoPort.postMessage( { action: 'goToAllPosts' } );
  				},
  				false
  			);
  
  			//overrides the all posts link just in case the user treats the link... as a link.
  			if ( calypsoifyGutenberg && calypsoifyGutenberg.closeUrl ) {
  				allPostsButton.setAttribute( 'target', '_parent' );
  				allPostsButton.setAttribute( 'href', calypsoifyGutenberg.closeUrl );
  			}
  
  			unsubscribe();
  		}
  	} );
  }
docs: Listens for post lock status changing to locked, and for the post to have been taken over
  by another user, adding an event handler for the All Posts button.
  
  @param {MessagePort} calypsoPort Port used for communication with parent frame.