From fc9b8de922e7ead161f353b01125e937d89eed03 Mon Sep 17 00:00:00 2001
From: Ryan Lue <hello@ryanlue.com>
Date: Mon, 29 Oct 2018 16:18:03 +0800
Subject: [PATCH] Ignore <img src="cid:..."> in forward-email text field (fixes
 #2305)

---
 app/assets/javascripts/app/lib/app_post/utils.coffee | 2 +-
 public/assets/tests/html_utils.js                    | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/app/assets/javascripts/app/lib/app_post/utils.coffee b/app/assets/javascripts/app/lib/app_post/utils.coffee
index 8eb83c257..44ae9459d 100644
--- a/app/assets/javascripts/app/lib/app_post/utils.coffee
+++ b/app/assets/javascripts/app/lib/app_post/utils.coffee
@@ -1146,7 +1146,7 @@ class App.Utils
 
     html.find('img').each( (index) ->
       src = $(@).attr('src')
-      if !src.match(/^data:/i)
+      if !src.match(/^(data|cid):/i) # <img src="cid: ..."> may mean broken emails (see issue #2305)
         base64 = App.Utils._htmlImage2DataUrl(@)
         $(@).attr('src', base64)
     )
diff --git a/public/assets/tests/html_utils.js b/public/assets/tests/html_utils.js
index e7ecd85eb..a9826538d 100644
--- a/public/assets/tests/html_utils.js
+++ b/public/assets/tests/html_utils.js
@@ -3079,6 +3079,11 @@ test("htmlImage2DataUrl", function() {
   result = App.Utils.htmlImage2DataUrl(source)
   equal(result, should, source)
 
+  source = '<img src="cid:1234">some test'
+  should = '<img src="cid:1234">some test'
+  result = App.Utils.htmlImage2DataUrl(source)
+  equal(result, should, source)
+
 });
 
 source = '<img src="/assets/images/avatar-bg.png">some test'