closes https://github.com/NodeBB/NodeBB/issues/3011

templates/composer.tpl

@@ -18,7 +18,7 @@
 				<!-- IF isTopicOrMain -->
 				<input class="title form-control" type="text" tabindex="1" placeholder="[[topic:composer.title_placeholder]]" value="{title}"/>
 				<!-- ELSE -->
-				<span class="title form-control">[[topic:composer.replying_to, "{title}"]]</span>
+				<span class="title form-control">[[topic:composer.replying_to, "{function.escape, title}"]]</span>
 				<!-- ENDIF isTopicOrMain -->
 			</div>
 			<!-- ELSE -->
@@ -26,7 +26,7 @@
 				<!-- IF isTopicOrMain -->
 				<input class="title form-control" type="text" tabindex="1" placeholder="[[topic:composer.title_placeholder]]" value="{title}"/>
 				<!-- ELSE -->
-				<span class="title form-control">[[topic:composer.replying_to, "{title}"]]</span>
+				<span class="title form-control">[[topic:composer.replying_to, "{function.escape, title}"]]</span>
 				<!-- ENDIF isTopicOrMain -->
 			</div>
 			<!-- IF isTopic -->