closes #3584

public/language/en_GB/topic.json

@@ -16,6 +16,7 @@
 	"notify_me": "Be notified of new replies in this topic",
 	"quote": "Quote",
 	"reply": "Reply",
+	"reply-as-topic": "Reply as topic",
 	"guest-login-reply": "Log in to reply",
 	"edit": "Edit",
 	"delete": "Delete",

public/src/client/topic/postTools.js

@@ -117,6 +117,12 @@ define('forum/topic/postTools', ['share', 'navigator', 'components', 'translator
 			onReplyClicked($(this), tid, topicName);
 		});
 
+		$('.topic').on('click', '[component="topic/reply-as-topic"]', function() {
+			$(window).trigger('action:composer.topic.new', {
+				cid: ajaxify.data.cid,
+			});
+		});
+
 		postContainer.on('click', '[component="post/favourite"]', function() {
 			favouritePost($(this), getData($(this), 'data-pid'));
 		});