make cancel post edit button link to the post in question

views/threads/post.etlua

@@ -72,7 +72,7 @@
         <% end %>
       <% else %>
         <% render("views.common.babycode-editor", {
-          cancel_url = post_url,
+          cancel_url = url_for("thread", {slug = thread.slug}, {after = post.id}) .. "#post-" .. post.id,
           prefill = post.original_markup,
           ta_name = "new_content"
           }) %>