diff --git a/OpenSim/Framework/AvatarAppearance.cs b/OpenSim/Framework/AvatarAppearance.cs
index 71e70e7b17..9c4b0c2ef0 100644
--- a/OpenSim/Framework/AvatarAppearance.cs
+++ b/OpenSim/Framework/AvatarAppearance.cs
@@ -916,18 +916,17 @@ namespace OpenSim.Framework
             {
                 // Wearables
                 OSD tmpOSD8;
-                OSDArray wears8 = null;
                 int wears8Count = 0;
 
-                if (data.TryGetValue("wrbls8", out tmpOSD8) && (tmpOSD8 is OSDArray))
+                if (data.TryGetValue("wrbls8", out tmpOSD8) && (tmpOSD8 is OSDArray wears8))
                 {
-                    wears8 = (OSDArray)tmpOSD8;
                     wears8Count = wears8.Count;
                 }
+                else
+                    wears8 = null;
 
-                if (data.TryGetValue("wearables", out tmpOSD) && (tmpOSD is OSDArray))
+                if (data.TryGetValue("wearables", out tmpOSD) && (tmpOSD is OSDArray wears))
                 {
-                    OSDArray wears = (OSDArray)tmpOSD;
                     if(wears.Count + wears8Count > 0)
                     {
                         m_wearables = new AvatarWearable[wears.Count + wears8Count];
@@ -948,9 +947,8 @@ namespace OpenSim.Framework
                     Primitive.TextureEntry te = new Primitive.TextureEntry(teb, 0, teb.Length);
                     m_texture = te;
                 }
-                else if (data.TryGetValue("textures", out tmpOSD) && (tmpOSD is OSDArray))
+                else if (data.TryGetValue("textures", out tmpOSD) && (tmpOSD is OSDArray textures))
                 {
-                    OSDArray textures = (OSDArray)tmpOSD;
                     for (int i = 0; i < textures.Count && i < TEXTURE_COUNT_PV7; ++i)
                     {
                         tmpOSD = textures[i];
@@ -959,26 +957,12 @@ namespace OpenSim.Framework
                     }
                 }
 
-                if (data.TryGetValue("bakedcache", out tmpOSD) && (tmpOSD is OSDArray))
+                if (data.TryGetValue("bakedcache", out tmpOSD) && (tmpOSD is OSDArray bakedOSDArray))
                 {
-                    OSDArray bakedOSDArray = (OSDArray)tmpOSD;
                     m_cacheitems = WearableCacheItem.GetDefaultCacheItem();
-
-                    bakedOSDArray = (OSDArray)tmpOSD;
-                    foreach (OSDMap item in bakedOSDArray)
+                    foreach (OSD oitem in bakedOSDArray)
                     {
-                        int idx = item["textureindex"].AsInteger();
-                        if (idx < 0 || idx >= m_cacheitems.Length)
-                            continue;
-                        m_cacheitems[idx].CacheId = item["cacheid"].AsUUID();
-                        m_cacheitems[idx].TextureID = item["textureid"].AsUUID();
-                        m_cacheitems[idx].TextureAsset = null;
-                    }
-
-                    if (data.TryGetValue("bc8", out tmpOSD) && (tmpOSD is OSDArray))
-                    {
-                        bakedOSDArray = (OSDArray)tmpOSD;
-                        foreach (OSDMap item in bakedOSDArray)
+                        if(oitem is OSDMap item)
                         {
                             int idx = item["textureindex"].AsInteger();
                             if (idx < 0 || idx >= m_cacheitems.Length)
@@ -988,6 +972,22 @@ namespace OpenSim.Framework
                             m_cacheitems[idx].TextureAsset = null;
                         }
                     }
+
+                    if (data.TryGetValue("bc8", out tmpOSD) && (tmpOSD is OSDArray))
+                    {
+                        foreach (OSD oitem in bakedOSDArray)
+                        {
+                            if(oitem is OSDMap item)
+                            {
+                                int idx = item["textureindex"].AsInteger();
+                                if (idx < 0 || idx >= m_cacheitems.Length)
+                                    continue;
+                                m_cacheitems[idx].CacheId = item["cacheid"].AsUUID();
+                                m_cacheitems[idx].TextureID = item["textureid"].AsUUID();
+                                m_cacheitems[idx].TextureAsset = null;
+                            }
+                        }
+                    }
                 }
 
                 // Visual Parameters
@@ -1002,9 +1002,8 @@ namespace OpenSim.Framework
                 }
 
                 // Attachments
-                if (data.TryGetValue("attachments", out tmpOSD) && tmpOSD is OSDArray)
+                if (data.TryGetValue("attachments", out tmpOSD) && tmpOSD is OSDArray attachs)
                 {
-                    OSDArray attachs = (OSDArray)tmpOSD;
                     for (int i = 0; i < attachs.Count; i++)
                     {
                         AvatarAttachment att = new AvatarAttachment((OSDMap)attachs[i]);
diff --git a/OpenSim/Framework/Lazy.cs b/OpenSim/Framework/Lazy.cs
index 44a7ba79fc..a364fedff1 100644
--- a/OpenSim/Framework/Lazy.cs
+++ b/OpenSim/Framework/Lazy.cs
@@ -81,8 +81,7 @@ namespace OpenSim.Framework
 
         public Lazy(Func<T> valueFactory, LazyThreadSafetyMode mode)
         {
-            if (valueFactory == null)
-                throw new ArgumentNullException("valueFactory");
+            ArgumentNullException.ThrowIfNull(valueFactory);
             this.factory = valueFactory;
             if (mode != LazyThreadSafetyMode.None)
                 monitor = new object();
diff --git a/OpenSim/Framework/Servers/HttpServer/BaseHttpServer.cs b/OpenSim/Framework/Servers/HttpServer/BaseHttpServer.cs
index 2b36f402c3..d1855114e6 100644
--- a/OpenSim/Framework/Servers/HttpServer/BaseHttpServer.cs
+++ b/OpenSim/Framework/Servers/HttpServer/BaseHttpServer.cs
@@ -212,6 +212,7 @@ namespace OpenSim.Framework.Servers.HttpServer
         {
             set { m_certificateValidationCallback = value; }
         }
+        private static readonly char[] LineSeparators = ['\n','\r'];
 
         private void load_cert(string CPath, string CPass)
         {
@@ -223,13 +224,13 @@ namespace OpenSim.Framework.Servers.HttpServer
                 {
                     AsnEncodedData asndata = new AsnEncodedData(ext.Oid, ext.RawData);
                     string datastr = asndata.Format(true);
-                    string[] lines = datastr.Split(new char[] {'\n','\r'});
+                    string[] lines = datastr.Split(LineSeparators);
                     foreach(string s in lines)
                     {
-                        if(String.IsNullOrEmpty(s))
+                        if(string.IsNullOrEmpty(s))
                             continue;
-                        string[] parts = s.Split(new char[] {'='});
-                        if(String.IsNullOrEmpty(parts[0]))
+                        string[] parts = s.Split('=');
+                        if(string.IsNullOrEmpty(parts[0]))
                             continue;
                         string entryName = parts[0].Replace(" ","");
                         if(entryName == "DNSName")
@@ -1015,8 +1016,7 @@ namespace OpenSim.Framework.Servers.HttpServer
             }
             finally
             {
-                if (innerStream != null)
-                    innerStream.Dispose();
+                innerStream?.Dispose();
                 inputStream.Dispose();
             }
         }
diff --git a/OpenSim/Framework/Servers/HttpServer/OSHttpServer/RequestCookie.cs b/OpenSim/Framework/Servers/HttpServer/OSHttpServer/RequestCookie.cs
index bededb9931..93dc129f43 100644
--- a/OpenSim/Framework/Servers/HttpServer/OSHttpServer/RequestCookie.cs
+++ b/OpenSim/Framework/Servers/HttpServer/OSHttpServer/RequestCookie.cs
@@ -22,7 +22,7 @@ namespace OSHttpServer
         public RequestCookie(string id, string content)
         {
             if (string.IsNullOrEmpty(id)) throw new ArgumentNullException("id");
-            if (content == null) throw new ArgumentNullException("content");
+            ArgumentNullException.ThrowIfNull(content);
 
             _name = id;
             _value = content;
diff --git a/OpenSim/Framework/Servers/HttpServer/RestSessionService.cs b/OpenSim/Framework/Servers/HttpServer/RestSessionService.cs
index a734997910..981b814e63 100644
--- a/OpenSim/Framework/Servers/HttpServer/RestSessionService.cs
+++ b/OpenSim/Framework/Servers/HttpServer/RestSessionService.cs
@@ -79,8 +79,10 @@ namespace OpenSim.Framework.Servers.HttpServer
 
             using (MemoryStream buffer = new MemoryStream())
             {
-                XmlWriterSettings settings = new XmlWriterSettings();
-                settings.Encoding = Encoding.UTF8;
+                XmlWriterSettings settings = new()
+                {
+                    Encoding = Encoding.UTF8
+                };
 
                 using (XmlWriter writer = XmlWriter.Create(buffer, settings))
                 {
@@ -134,8 +136,7 @@ namespace OpenSim.Framework.Servers.HttpServer
 
             using (MemoryStream buffer = new MemoryStream())
             {
-                XmlWriterSettings settings = new XmlWriterSettings();
-                settings.Encoding = Encoding.UTF8;
+                XmlWriterSettings settings = new() { Encoding = Encoding.UTF8 };
 
                 using (XmlWriter writer = XmlWriter.Create(buffer, settings))
                 {
@@ -169,8 +170,7 @@ namespace OpenSim.Framework.Servers.HttpServer
                 //                m_log.DebugFormat("[REST OBJECT POSTER RESPONSE]: Received {0}", reader.ReadToEnd());
 
                 deserial = (TResponse)deserializer.Deserialize(stream);
-                if (stream != null)
-                    stream.Close();
+                stream?.Close();
 
                 if (deserial != null && ResponseCallback != null)
                 {
diff --git a/OpenSim/Framework/WebUtil.cs b/OpenSim/Framework/WebUtil.cs
index 37d0e8c2eb..d8ef2dc77f 100644
--- a/OpenSim/Framework/WebUtil.cs
+++ b/OpenSim/Framework/WebUtil.cs
@@ -1009,8 +1009,7 @@ namespace OpenSim.Framework
 
             HttpWebRequest request = (HttpWebRequest)WebRequest.Create(requestUrl);
 
-            if (auth != null)
-                auth.AddAuthorization(request.Headers);
+            auth?.AddAuthorization(request.Headers);
 
             request.AllowWriteStreamBuffering = false;
 
diff --git a/OpenSim/Region/ClientStack/Linden/UDP/LLUDPServer.cs b/OpenSim/Region/ClientStack/Linden/UDP/LLUDPServer.cs
index 7fc85b0d72..69a7f4e110 100755
--- a/OpenSim/Region/ClientStack/Linden/UDP/LLUDPServer.cs
+++ b/OpenSim/Region/ClientStack/Linden/UDP/LLUDPServer.cs
@@ -1535,10 +1535,7 @@ namespace OpenSim.Region.ClientStack.LindenUDP
                 catch (Exception ex)
                 {
                     m_log.Error($"Packet statistics gathering failed: {ex.Message}");
-                    if (PacketLog.Log != null)
-                    {
-                        PacketLog.Log.Close();
-                    }
+                    PacketLog?.Log?.Close();
                     PacketLog = null;
                 }
             }
diff --git a/OpenSim/Region/ClientStack/Linden/UDP/TokenBucket.cs b/OpenSim/Region/ClientStack/Linden/UDP/TokenBucket.cs
index 750096de7d..4c44181217 100644
--- a/OpenSim/Region/ClientStack/Linden/UDP/TokenBucket.cs
+++ b/OpenSim/Region/ClientStack/Linden/UDP/TokenBucket.cs
@@ -226,8 +226,7 @@ namespace OpenSim.Region.ClientStack.LindenUDP
             }
 
             // Pass the new values up to the parent
-            if (m_parent != null)
-                m_parent.RegisterRequest(this, Math.Min(RequestedDripRate, TotalDripRequest));
+            m_parent?.RegisterRequest(this, Math.Min(RequestedDripRate, TotalDripRequest));
         }
 
         /// <summary>
@@ -246,8 +245,7 @@ namespace OpenSim.Region.ClientStack.LindenUDP
             }
 
             // Pass the new values up to the parent
-            if (Parent != null)
-                Parent.RegisterRequest(this,Math.Min(RequestedDripRate, TotalDripRequest));
+            Parent?.RegisterRequest(this,Math.Min(RequestedDripRate, TotalDripRequest));
         }
 
         /// <summary>
@@ -351,8 +349,7 @@ namespace OpenSim.Region.ClientStack.LindenUDP
             {
                 m_dripRate = Math.Clamp(value, m_minimumFlow, MaxDripRate);
 
-                if (m_parent != null)
-                    m_parent.RegisterRequest(this, m_dripRate);
+                m_parent?.RegisterRequest(this, m_dripRate);
             }
         }
 
@@ -371,8 +368,7 @@ namespace OpenSim.Region.ClientStack.LindenUDP
                 m_dripRate = m_maxDripRate * .5f;
             else
                 m_dripRate = m_maxDripRate;
-            if (m_parent != null)
-                m_parent.RegisterRequest(this, m_dripRate);
+            m_parent?.RegisterRequest(this, m_dripRate);
         }
 
         /// <summary>
@@ -392,7 +388,7 @@ namespace OpenSim.Region.ClientStack.LindenUDP
         public void AcknowledgePackets(Int32 count)
         {
             if (m_enabled)
-                AdjustedDripRate = AdjustedDripRate + count;
+                AdjustedDripRate += count;
         }
     }
 }
diff --git a/OpenSim/Region/CoreModules/World/Wind/WindModule.cs b/OpenSim/Region/CoreModules/World/Wind/WindModule.cs
index 027d43243d..240c07ff21 100755
--- a/OpenSim/Region/CoreModules/World/Wind/WindModule.cs
+++ b/OpenSim/Region/CoreModules/World/Wind/WindModule.cs
@@ -105,11 +105,9 @@ namespace OpenSim.Region.CoreModules
             }
 
             // Check for desired plugin
-            if (m_availableWindPlugins.ContainsKey(m_dWindPluginName))
+            if (m_availableWindPlugins.TryGetValue(m_dWindPluginName, out m_activeWindPlugin))
             {
-                m_activeWindPlugin = m_availableWindPlugins[m_dWindPluginName];
-
-                m_log.InfoFormat("[WIND] {0} plugin found, initializing.", m_dWindPluginName);
+                 m_log.InfoFormat("[WIND] {0} plugin found, initializing.", m_dWindPluginName);
 
                 if (m_windConfig != null)
                 {
diff --git a/OpenSim/Region/PhysicsModules/ubOde/ODEModule.cs b/OpenSim/Region/PhysicsModules/ubOde/ODEModule.cs
index ed9c85921b..81352aae40 100644
--- a/OpenSim/Region/PhysicsModules/ubOde/ODEModule.cs
+++ b/OpenSim/Region/PhysicsModules/ubOde/ODEModule.cs
@@ -123,8 +123,7 @@ namespace OpenSim.Region.PhysicsModule.ubOde
             if (!m_Enabled)
                 return;
 
-            if(m_odeScene != null)
-                m_odeScene.RegionLoaded();
+            m_odeScene?.RegionLoaded();
 
         }
         #endregion
diff --git a/OpenSim/Region/PhysicsModules/ubOdeMeshing/Meshmerizer.cs b/OpenSim/Region/PhysicsModules/ubOdeMeshing/Meshmerizer.cs
index e524724228..4ff2639301 100644
--- a/OpenSim/Region/PhysicsModules/ubOdeMeshing/Meshmerizer.cs
+++ b/OpenSim/Region/PhysicsModules/ubOdeMeshing/Meshmerizer.cs
@@ -1331,8 +1331,7 @@ namespace OpenSim.Region.PhysicsModule.ubODEMeshing
                 }
                 finally
                 {
-                    if(stream != null)
-                        stream.Dispose();
+                    stream?.Dispose();
                 }
 
                 if (!ok && File.Exists(filename))
diff --git a/OpenSim/Services/AssetService/AssetService.cs b/OpenSim/Services/AssetService/AssetService.cs
index ed6580ff64..e648df6574 100644
--- a/OpenSim/Services/AssetService/AssetService.cs
+++ b/OpenSim/Services/AssetService/AssetService.cs
@@ -61,8 +61,7 @@ namespace OpenSim.Services.AssetService
                     if (assetConfig == null)
                         throw new Exception("No " + m_ConfigName + " configuration");
 
-                    string loaderArgs = assetConfig.GetString("AssetLoaderArgs",
-                            String.Empty);
+                    string loaderArgs = assetConfig.GetString("AssetLoaderArgs", string.Empty);
 
                     bool assetLoaderEnabled = assetConfig.GetBoolean("AssetLoaderEnabled", true);
 
@@ -92,11 +91,8 @@ namespace OpenSim.Services.AssetService
 
         public virtual AssetBase Get(string id)
         {
-//            m_log.DebugFormat("[ASSET SERVICE]: Get asset for {0}", id);
-
-            UUID assetID;
-
-            if (!UUID.TryParse(id, out assetID))
+            //            m_log.DebugFormat("[ASSET SERVICE]: Get asset for {0}", id);
+            if (!UUID.TryParse(id, out UUID assetID))
             {
                 m_log.WarnFormat("[ASSET SERVICE]: Could not parse requested asset id {0}", id);
                 return null;