src/vs/workbench/contrib/extensions/browser/extensionEditor.ts/ExtensionEditor/openReadme
class ExtensionEditor:	private async openReadme(template: IExtensionEditorTemplate, token: CancellationToken): Promise<IActiveElement | null> {
		const manifest = await this.extensionManifest!.get().promise;
		if (manifest && manifest.extensionPack?.length && this.shallRenderAsExensionPack(manifest)) {
			return this.openExtensionPackReadme(manifest, template, token);
		}
		return this.openMarkdown(this.extensionReadme!.get(), localize('noReadme', "No README available."), template, WebviewIndex.Readme, token);
	}