src/vs/workbench/contrib/webviewView/browser/webviewViewPane.ts/WebviewViewPane/renderBody
class WebviewViewPane:	override renderBody(container: HTMLElement): void {
		super.renderBody(container);

		this._container = container;
		this._rootContainer = undefined;

		if (!this._resizeObserver) {
			this._resizeObserver = new ResizeObserver(() => {
				setTimeout(() => {
					this.layoutWebview();
				}, 0);
			});

			this._register(toDisposable(() => {
				this._resizeObserver.disconnect();
			}));
			this._resizeObserver.observe(container);
		}
	}