src/vs/workbench/browser/parts/panel/panelPart.ts/PanelPart/createEmptyPanelMessage
class PanelPart:	private createEmptyPanelMessage(): void {
		const contentArea = this.getContentArea()!;
		this.emptyPanelMessageElement = document.createElement('div');
		this.emptyPanelMessageElement.classList.add('empty-panel-message-area');

		const messageElement = document.createElement('div');
		messageElement.classList.add('empty-panel-message');
		messageElement.innerText = localize('panel.emptyMessage', "Drag a view into the panel to display.");

		this.emptyPanelMessageElement.appendChild(messageElement);
		contentArea.appendChild(this.emptyPanelMessageElement);

		this._register(CompositeDragAndDropObserver.INSTANCE.registerTarget(this.emptyPanelMessageElement, {
			onDragOver: (e) => {
				EventHelper.stop(e.eventData, true);
				const validDropTarget = this.dndHandler.onDragEnter(e.dragAndDropData, undefined, e.eventData);
				toggleDropEffect(e.eventData.dataTransfer, 'move', validDropTarget);
			},
			onDragEnter: (e) => {
				EventHelper.stop(e.eventData, true);

				const validDropTarget = this.dndHandler.onDragEnter(e.dragAndDropData, undefined, e.eventData);
				this.emptyPanelMessageElement!.style.backgroundColor = validDropTarget ? this.theme.getColor(EDITOR_DRAG_AND_DROP_BACKGROUND)?.toString() || '' : '';
			},
			onDragLeave: (e) => {
				EventHelper.stop(e.eventData, true);
				this.emptyPanelMessageElement!.style.backgroundColor = '';
			},
			onDragEnd: (e) => {
				EventHelper.stop(e.eventData, true);
				this.emptyPanelMessageElement!.style.backgroundColor = '';
			},
			onDrop: (e) => {
				EventHelper.stop(e.eventData, true);
				this.emptyPanelMessageElement!.style.backgroundColor = '';

				this.dndHandler.drop(e.dragAndDropData, undefined, e.eventData);
			},
		}));
	}