diff --git a/OpenSim/Region/CoreModules/Avatar/Friends/FriendsModule.cs b/OpenSim/Region/CoreModules/Avatar/Friends/FriendsModule.cs
index b224f878c2..6d08b7bcf6 100644
--- a/OpenSim/Region/CoreModules/Avatar/Friends/FriendsModule.cs
+++ b/OpenSim/Region/CoreModules/Avatar/Friends/FriendsModule.cs
@@ -268,11 +268,14 @@ namespace OpenSim.Region.CoreModules.Avatar.Friends
                 friends = new HashSet<UUID>();
                 m_OnlineFriendsCache[userID] = friends;
             }
-            foreach (UUID friendID in friendsOnline)
+            if (online)
             {
-                if (online)
+                foreach (UUID friendID in friendsOnline)
                     friends.Add(friendID);
-                else
+            }
+            else
+            {
+                foreach (UUID friendID in friendsOnline)
                     friends.Remove(friendID);
             }
         }
@@ -374,6 +377,8 @@ namespace OpenSim.Region.CoreModules.Avatar.Friends
 
             lock (m_Friends)
             {
+                foreach(HashSet<UUID> friends in m_OnlineFriendsCache.Values)
+                    friends.Remove(agentID);
                 m_OnlineFriendsCache.Remove(agentID);
                 if (m_Friends.TryGetValue(agentID, out UserFriendData friendsData))
                 {
diff --git a/OpenSim/Region/CoreModules/Avatar/Friends/HGFriendsModule.cs b/OpenSim/Region/CoreModules/Avatar/Friends/HGFriendsModule.cs
index 6510824868..4e95a456ab 100644
--- a/OpenSim/Region/CoreModules/Avatar/Friends/HGFriendsModule.cs
+++ b/OpenSim/Region/CoreModules/Avatar/Friends/HGFriendsModule.cs
@@ -238,10 +238,22 @@ namespace OpenSim.Region.CoreModules.Avatar.Friends
             // FIXME: also query the presence status of friends in other grids (like in HGStatusNotifier.Notify())
 
             PresenceInfo[] presence = PresenceService.GetAgents(fList.ToArray());
+            if (presence.Length == 0)
+                return;
+
+            if (!m_OnlineFriendsCache.TryGetValue(userID, out HashSet<UUID> friends))
+            {
+                friends = new HashSet<UUID>();
+                m_OnlineFriendsCache[userID] = friends;
+            }
+
             foreach (PresenceInfo pi in presence)
             {
                 if (UUID.TryParse(pi.UserID, out UUID presenceID))
+                {
                     online.Add(presenceID);
+                    friends.Add(presenceID);
+                }
             }
 
             //m_log.DebugFormat("[HGFRIENDS MODULE]: Exiting GetOnlineFriends for {0}", userID);
diff --git a/OpenSim/Region/CoreModules/Avatar/UserProfiles/UserProfileModule.cs b/OpenSim/Region/CoreModules/Avatar/UserProfiles/UserProfileModule.cs
index d12525e659..09156d71f2 100644
--- a/OpenSim/Region/CoreModules/Avatar/UserProfiles/UserProfileModule.cs
+++ b/OpenSim/Region/CoreModules/Avatar/UserProfiles/UserProfileModule.cs
@@ -1842,7 +1842,7 @@ namespace OpenSim.Region.CoreModules.Avatar.UserProfiles
             if(client.SceneAgent is ScenePresence sp && sp.IsViewerUIGod)
             {
                 Services.Interfaces.PresenceInfo[] pi = Scene.PresenceService?.GetAgents(new string[] { agent.ToString() });
-                return pi != null && pi.Length > 0;
+                return pi is not null && pi.Length > 0;
             }
             return false;
          }