diff --git a/tpl/tplimpl/embedded/templates/schema.html b/tpl/tplimpl/embedded/templates/schema.html
index c4e89abd6e9..2b3c5425aeb 100644
--- a/tpl/tplimpl/embedded/templates/schema.html
+++ b/tpl/tplimpl/embedded/templates/schema.html
@@ -1,8 +1,8 @@
-{{- with or .Title site.Title }}
+{{- with or .Title site.Title | plainify }}
{{- end }}
-{{- with or .Description .Summary site.Params.Description }}
+{{- with or .Description .Summary site.Params.description | plainify | htmlUnescape | chomp }}
{{- end }}
diff --git a/tpl/tplimpl/tplimpl_integration_test.go b/tpl/tplimpl/tplimpl_integration_test.go
index f9d25eb49f3..b30965be938 100644
--- a/tpl/tplimpl/tplimpl_integration_test.go
+++ b/tpl/tplimpl/tplimpl_integration_test.go
@@ -411,3 +411,85 @@ series: [series-1]
``,
)
}
+
+// Issue 12432
+func TestSchema(t *testing.T) {
+ t.Parallel()
+
+ files := `
+-- hugo.toml --
+capitalizeListTitles = false
+disableKinds = ['rss','sitemap']
+[markup.goldmark.renderer]
+unsafe = true
+[params]
+description = "m n and **o** can't."
+[taxonomies]
+tag = 'tags'
+-- layouts/_default/list.html --
+{{ template "_internal/schema.html" . }}
+-- layouts/_default/single.html --
+{{ template "_internal/schema.html" . }}
+-- content/s1/p1.md --
+---
+title: p1
+date: 2024-04-24T08:00:00-07:00
+lastmod: 2024-04-24T11:00:00-07:00
+images: [a.jpg,b.jpg]
+tags: [t1,t2]
+---
+a b and **c** can't.
+-- content/s1/p2.md --
+---
+title: p2
+---
+d e and **f** can't.
+
+-- content/s1/p3.md --
+---
+title: p3
+summary: g h and **i** can't.
+---
+-- content/s1/p4.md --
+---
+title: p4
+description: j k and **l** can't.
+---
+-- content/s1/p5.md --
+---
+title: p5
+---
+`
+
+ b := hugolib.Test(t, files)
+
+ b.AssertFileContent("public/s1/p1/index.html", `
+
+
+
+
+
+
+
+
+ `,
+ )
+
+ b.AssertFileContent("public/s1/p2/index.html",
+ ``,
+ )
+
+ b.AssertFileContent("public/s1/p3/index.html",
+ ``,
+ )
+
+ // The markdown is intentionally not rendered to HTML.
+ b.AssertFileContent("public/s1/p4/index.html",
+ ``,
+ )
+
+ // The markdown is intentionally not rendered to HTML.
+ b.AssertFileContent("public/s1/p5/index.html",
+ ``,
+ )
+}