diff --git a/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldRemarkup.php b/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldRemarkup.php
--- a/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldRemarkup.php
+++ b/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldRemarkup.php
@@ -19,6 +19,13 @@
     return 'block';
   }
 
+  public function getApplicationTransactionRemarkupBlocks(
+    PhabricatorApplicationTransaction $xaction) {
+    return array(
+      $xaction->getNewValue(),
+    );
+  }
+
   public function renderPropertyViewValue(array $handles) {
     $value = $this->getFieldValue();
 
diff --git a/src/infrastructure/markup/PhabricatorMarkupEngine.php b/src/infrastructure/markup/PhabricatorMarkupEngine.php
--- a/src/infrastructure/markup/PhabricatorMarkupEngine.php
+++ b/src/infrastructure/markup/PhabricatorMarkupEngine.php
@@ -530,13 +530,15 @@
 
     foreach ($content_blocks as $content_block) {
       $engine->markupText($content_block);
-      $ids = $engine->getTextMetadata(
+      $phids = $engine->getTextMetadata(
         PhabricatorEmbedFileRemarkupRule::KEY_EMBED_FILE_PHIDS,
         array());
-      $files += $ids;
+      foreach ($phids as $phid) {
+        $files[$phid] = $phid;
+      }
     }
 
-    return $files;
+    return array_values($files);
   }
 
   /**