diff --git a/Signal/src/ViewControllers/MediaGalleryViewController.swift b/Signal/src/ViewControllers/MediaGalleryViewController.swift
index c1bf2908c3..86cc9bb7f1 100644
--- a/Signal/src/ViewControllers/MediaGalleryViewController.swift
+++ b/Signal/src/ViewControllers/MediaGalleryViewController.swift
@@ -342,8 +342,7 @@ class MediaGalleryViewController: OWSNavigationController, MediaGalleryDataSourc
         detailView.backgroundColor = .clear
         self.view.backgroundColor = .clear
 
-        // TODO: Sync with (possibly assymetrical) corner rounding in message bubbles.
-        self.presentationView.layer.cornerRadius = kOWSMessageCellCornerRadius_Large
+        self.presentationView.layer.cornerRadius = kOWSMessageCellCornerRadius_Small
 
         fromViewController.present(self, animated: false) {
 
diff --git a/Signal/src/ViewControllers/MessageDetailViewController.swift b/Signal/src/ViewControllers/MessageDetailViewController.swift
index d32c10745b..659eacbb83 100644
--- a/Signal/src/ViewControllers/MessageDetailViewController.swift
+++ b/Signal/src/ViewControllers/MessageDetailViewController.swift
@@ -254,6 +254,9 @@ class MessageDetailViewController: OWSViewController, MediaGalleryDataSourceDele
                     // Table view cells don't layout properly outside the
                     // context of a table view.
                     let cellView = ContactCellView()
+                    // canary in case we later add margins in the ContactCellView initializer.
+                    assert(!cellView.isLayoutMarginsRelativeArrangement)
+                    cellView.isLayoutMarginsRelativeArrangement = true
                     cellView.layoutMargins = UIEdgeInsets(top: 8, left: 20, bottom: 8, right: 20)
                     // We use the "short" status message to avoid being redundant with the section title.
                     cellView.accessoryMessage = shortStatusMessage