fix(NetworkInformationPreview): NRE in constructor (#4034)

* Fix EditorStyles.label causing NRE in NetworkInformationPreview implicit constructor

* Update Assets/Mirror/Editor/NetworkInformationPreview.cs

---------

Co-authored-by: Liam Cary <[email protected]>
Co-authored-by: mischa <[email protected]>

Author: 3 people

Assets/Mirror/Editor/NetworkInformationPreview.cs

@@ -60,7 +60,11 @@ public Styles()
         }
 
         GUIContent title;
-        Styles styles = new Styles();
+
+        // Lazy-init fixes NullReferenceException from Styles.labelStyle accessing EditorStyles.label before unity initialises EditorStyles.s_Current
+        // https://github.com/MirrorNetworking/Mirror/pull/4034
+        Styles _styles;
+        Styles styles => _styles ?? (_styles = new Styles());
 
         public override GUIContent GetPreviewTitle()
         {
@@ -95,10 +99,6 @@ public override void OnPreviewGUI(Rect r, GUIStyle background)
             if (identity == null)
                 return;
 
-            if (styles == null)
-                styles = new Styles();
-
-
             // padding
             RectOffset previewPadding = new RectOffset(-5, -5, -5, -5);
             Rect paddedr = previewPadding.Add(r);