src/vs/workbench/contrib/extensions/browser/extensionEditor.ts/ExtensionEditor/renderIconThemes
class ExtensionEditor:	private renderIconThemes(container: HTMLElement, manifest: IExtensionManifest, onDetailsToggle: Function): boolean {
		const contrib = manifest.contributes?.iconThemes || [];
		if (!contrib.length) {
			return false;
		}

		const details = $('details', { open: true, ontoggle: onDetailsToggle },
			$('summary', { tabindex: '0' }, localize('iconThemes', "File Icon Themes ({0})", contrib.length)),
			$('ul', undefined, ...contrib.map(theme => $('li', undefined, theme.label)))
		);

		append(container, details);
		return true;
	}