diff --git a/CHANGES.rst b/CHANGES.rst
index a1ec981a5..f63e1e213 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -2,6 +2,7 @@ Changes in 0.11.0 (2020-xx-xx)
 ===============================================
 
 Improvements:
+ * E2E: Do not warn anymore for unknown devices
  * ON/OFF Cross-signing development in a Lab setting (#2855).
  * RoomVC: Update encryption decoration with shields (#2934, #2930, #2906).
  * Settings: Remove "End-to-End Encryption" from the LABS section (#2941).
diff --git a/Riot/AppDelegate.m b/Riot/AppDelegate.m
index f0915efcc..6200418e2 100644
--- a/Riot/AppDelegate.m
+++ b/Riot/AppDelegate.m
@@ -2802,6 +2802,9 @@ NSString *const AppDelegateDidValidateEmailNotificationClientSecretKey = @"AppDe
                     break;
                 }
             }
+            
+            // Do not warn for unknown devices if cross-signing is enabled
+            mxSession.crypto.warnOnUnknowDevices = !RiotSettings.shared.enableCrossSigning;
         }
         else if (mxSession.state == MXSessionStateClosed)
         {
diff --git a/Riot/Modules/Settings/SettingsViewController.m b/Riot/Modules/Settings/SettingsViewController.m
index a65477d66..dd5c79285 100644
--- a/Riot/Modules/Settings/SettingsViewController.m
+++ b/Riot/Modules/Settings/SettingsViewController.m
@@ -3056,6 +3056,8 @@ SettingsIdentityServerCoordinatorBridgePresenterDelegate>
     UISwitch *switchButton = (UISwitch*)sender;
     
     RiotSettings.shared.enableCrossSigning = switchButton.isOn;
+    
+    self.mainSession.crypto.warnOnUnknowDevices = !RiotSettings.shared.enableCrossSigning;
 }
 
 - (void)togglePinRoomsWithMissedNotif:(id)sender