diff --git a/Signal/src/ViewControllers/MediaPageViewController.swift b/Signal/src/ViewControllers/MediaPageViewController.swift
index a4df3da2f..0a3287dc3 100644
--- a/Signal/src/ViewControllers/MediaPageViewController.swift
+++ b/Signal/src/ViewControllers/MediaPageViewController.swift
@@ -23,6 +23,12 @@ class MediaPageViewController: UIPageViewController, UIPageViewControllerDataSou
 
             return image
         }
+
+        // MARK: Equatable
+
+        static func == (lhs: MediaGalleryItem, rhs: MediaGalleryItem) -> Bool {
+            return lhs.message.uniqueId == rhs.message.uniqueId
+        }
     }
 
     private var cachedItems: [MediaGalleryItem] = []