diff --git a/src/applications/conpherence/storage/ConpherenceThread.php b/src/applications/conpherence/storage/ConpherenceThread.php
--- a/src/applications/conpherence/storage/ConpherenceThread.php
+++ b/src/applications/conpherence/storage/ConpherenceThread.php
@@ -204,17 +204,18 @@
     }
 
     $user_participation = $this->getParticipantIfExists($viewer->getPHID());
-    $theme_class = ConpherenceRoomSettings::COLOR_LIGHT;
+    $theme = ConpherenceRoomSettings::COLOR_LIGHT;
     if ($user_participation) {
       $user_seen_count = $user_participation->getSeenMessageCount();
       $participant = $this->getParticipant($viewer->getPHID());
       $settings = $participant->getSettings();
       $theme = idx($settings, 'theme', $theme);
-      $theme_class = ConpherenceRoomSettings::getThemeClass($theme);
     } else {
       $user_seen_count = 0;
     }
+
     $unread_count = $this->getMessageCount() - $user_seen_count;
+    $theme_class = ConpherenceRoomSettings::getThemeClass($theme);
 
     $title = $this->getTitle();
     $topic = $this->getTopic();