diff --git a/modules/markup/markdown/markdown_test.go b/modules/markup/markdown/markdown_test.go
index b2cf529964091..f44c0acb96131 100644
--- a/modules/markup/markdown/markdown_test.go
+++ b/modules/markup/markdown/markdown_test.go
@@ -93,6 +93,12 @@ func TestRender_Images(t *testing.T) {
 	test(
 		"[!["+title+"]("+url+")]("+href+")",
 		`<p><a href="`+href+`" rel="nofollow"><img src="`+result+`" alt="`+title+`"/></a></p>`)
+	test(
+		"!["+title+"]("+url+" \"1 -> 2 -> 3 -> 4 -> 5\")",
+		`<p><a href="`+result+`" title="1 -&gt; 2 -&gt; 3 -&gt; 4 -&gt; 5" rel="nofollow"><img src="`+result+`" alt="`+title+`"/></a></p>`)
+	test(
+		"!["+title+"]("+url+" \"this?is#a!test:P\")",
+		`<p><a href="`+result+`" title="this?is#a!test:P" rel="nofollow"><img src="`+result+`" alt="`+title+`"/></a></p>`)
 }
 
 func testAnswers(baseURLContent, baseURLImages string) []string {
diff --git a/modules/markup/sanitizer.go b/modules/markup/sanitizer.go
index 49f681f05a1e6..00e7ccfc717f5 100644
--- a/modules/markup/sanitizer.go
+++ b/modules/markup/sanitizer.go
@@ -56,6 +56,9 @@ func ReplaceSanitizer() {
 	// Allow classes for anchors
 	sanitizer.policy.AllowAttrs("class").Matching(regexp.MustCompile(`ref-issue`)).OnElements("a")
 
+	// Allow more characters in title attribute per commonmark spec
+	sanitizer.policy.AllowAttrs("title").Matching(regexp.MustCompile(`(.*?)`)).OnElements("a")
+
 	// Custom keyword markup
 	for _, rule := range setting.ExternalSanitizerRules {
 		if rule.Regexp != nil {