var html/template.fmtStringerType

2 uses

	html/template (current package)
		content.go#L132: 	fmtStringerType = reflect.TypeOf((*fmt.Stringer)(nil)).Elem()
		content.go#L143: 	for !v.Type().Implements(fmtStringerType) && !v.Type().Implements(errorType) && v.Kind() == reflect.Pointer && !v.IsNil() {