diff --git a/tpl/tplimpl/embedded/templates/shortcodes/details.html b/tpl/tplimpl/embedded/templates/shortcodes/details.html
index c19d78c3e..82c4f68f7 100644
--- a/tpl/tplimpl/embedded/templates/shortcodes/details.html
+++ b/tpl/tplimpl/embedded/templates/shortcodes/details.html
@@ -68,7 +68,7 @@ Renders an HTML details element.
   {{- with $class }} class="{{ . }}" {{- end }}
   {{- with $name }} name="{{ . }}" {{- end }}
   {{- with $open }} open {{- end }}
-  {{- with $title }} class="{{ . }}" {{- end -}}
+  {{- with $title }} title="{{ . }}" {{- end -}}
 >
   <summary>{{ $summary | .Page.RenderString }}</summary>
   {{ .Inner | .Page.RenderString (dict "display" "block") -}}
diff --git a/tpl/tplimpl/tplimpl_integration_test.go b/tpl/tplimpl/tplimpl_integration_test.go
index 445316a0a..1e7aa3111 100644
--- a/tpl/tplimpl/tplimpl_integration_test.go
+++ b/tpl/tplimpl/tplimpl_integration_test.go
@@ -643,7 +643,7 @@ E: An _emphasized_ word.
 
 	b.AssertFileContent("public/index.html",
 		"<details>\n  <summary>Details</summary>\n  <p>A: An <em>emphasized</em> word.</p>\n</details>",
-		"<details class=\"my-class\" name=\"my-name\" open class=\"my-title\">\n  <summary>A <strong>bold</strong> word</summary>\n  <p>B: An <em>emphasized</em> word.</p>\n</details>",
+		"<details class=\"my-class\" name=\"my-name\" open title=\"my-title\">\n  <summary>A <strong>bold</strong> word</summary>\n  <p>B: An <em>emphasized</em> word.</p>\n</details>",
 		"<details>\n  <summary>Details</summary>\n  <p>C: An <em>emphasized</em> word.</p>\n</details>",
 		"<details>\n  <summary>Details</summary>\n  <p>D: An <em>emphasized</em> word.</p>\n</details>",
 		"<details>\n  <summary>Details</summary>\n  <p>D: An <em>emphasized</em> word.</p>\n</details>",