src/vs/workbench/browser/parts/sidebar/sidebarPart.ts/SidebarPart/openPaneComposite
class SidebarPart:	async openPaneComposite(id: string | undefined, focus?: boolean): Promise<IPaneComposite | undefined> {
		if (typeof id === 'string' && this.getPaneComposite(id)) {
			return this.doOpenViewlet(id, focus);
		}

		await this.extensionService.whenInstalledExtensionsRegistered();

		if (typeof id === 'string' && this.getPaneComposite(id)) {
			return this.doOpenViewlet(id, focus);
		}

		return undefined;
	}