its';
					}
				});

				// Remove the "select1" field from the "tab1" tab.
				infoTab.remove( 'select1' );

				// Set the default value for "input1" field.
				var input1 = infoTab.get( 'input1' );
				input1[ 'default' ] = 'www.example.com';

				// Remove the "tab2" tab page.
				dialogDefinition.removeContents( 'tab2' );

				// Add a new tab to the "Link" dialog.
				dialogDefinition.addContents( {
					id: 'customTab',
					label: 'My Tab',
					accessKey: 'M',
					elements: [
						{
							id: '