fix iframe autoclosing

src/content/sanitizer/sanitizer.go

@@ -69,8 +69,12 @@ func Sanitize(baseURL, input string) string {
 						buffer.WriteString("<" + tagName + ">")
 					}
 
-					if wrap {
+					if tagName == "iframe" {
-						buffer.WriteString("</iframe></div>")
+						// autoclose iframes
+						buffer.WriteString("</iframe>")
+						if wrap {
+							buffer.WriteString("</div>")
+						}
 					} else {
 						tagStack = append(tagStack, tagName)
 					}
@@ -80,6 +84,7 @@ func Sanitize(baseURL, input string) string {
 			}
 		case html.EndTagToken:
 			tagName := token.Data
+			// iframes are autoclosed. see above
 			if tagName == "iframe" {
 				continue
 			}

src/content/sanitizer/sanitizer_test.go

@@ -163,6 +163,16 @@ func TestInvalidNestedTag(t *testing.T) {
 	}
 }
 
+func TestValidIFrame(t *testing.T) {
+	input := `<iframe src="http://example.org/"></iframe>`
+	expected := `<iframe src="http://example.org/" sandbox="allow-scripts allow-same-origin allow-popups" loading="lazy"></iframe>`
+	output := Sanitize("http://example.org/", input)
+
+	if expected != output {
+		t.Errorf("Wrong output:\nwant: %s\nhave: %s", expected, output)
+	}
+}
+
 func TestInvalidIFrame(t *testing.T) {
 	input := `<iframe src="http://example.org/"></iframe>`
 	expected := ``