src/vs/workbench/contrib/preferences/browser/settingsTree.ts/SettingComplexRenderer/renderValidations
class SettingComplexRenderer:	private renderValidations(dataElement: SettingsTreeSettingElement, template: ISettingComplexItemTemplate) {
		const errMsg = dataElement.isConfigured && getInvalidTypeError(dataElement.value, dataElement.setting.type);
		if (errMsg) {
			template.containerElement.classList.add('invalid-input');
			template.validationErrorMessageElement.innerText = errMsg;
			return;
		}

		template.containerElement.classList.remove('invalid-input');
	}