FEATURE: keep formatting when quoting

app/assets/javascripts/application.js

@@ -9,6 +9,8 @@
 //= require ./deprecated
 
 // Stuff we need to load first
+//= require ./discourse/helpers/parse-html
+//= require ./discourse/lib/to-markdown
 //= require ./discourse/lib/utilities
 //= require ./discourse/lib/page-visible
 //= require ./discourse/lib/logout

app/assets/javascripts/discourse/controllers/topic.js.es6

@@ -131,7 +131,6 @@ export default Ember.Controller.extend(BufferedContent, {
       return this.get('model.postStream').loadPost(postId).then(post => {
         const composer = this.get('composer');
         const viewOpen = composer.get('model.viewOpen');
-
         const quotedText = Quote.build(post, buffer);
 
         // If we can't create a post, delegate to reply as new topic

app/assets/javascripts/discourse/lib/utilities.js.es6

@@ -1,4 +1,5 @@
 import { escape } from 'pretty-text/sanitizer';
+import toMarkdown from 'discourse/lib/to-markdown';
 
 const homepageSelector = 'meta[name=discourse_current_homepage]';
 
@@ -113,12 +114,8 @@ export function selectedText() {
   $div.find(".clicks").remove();
   // replace emojis
   $div.find("img.emoji").replaceWith(function() { return this.title; });
-  // replace br with newlines
-  $div.find("br").replaceWith(() => "\n");
-  // enforce newline at the end of paragraphs
-  $div.find("p").append(() => "\n");
 
-  return String($div.text()).trim().replace(/(^\s*\n)+/gm, "\n");
+  return toMarkdown($div.html());
 }
 
 // Determine the row and col of the caret in an element