Upgraded the UITK preview version to 12. Changed ScaleMode on the PanelSettings to better fit the UI.

Assets/UI/UnityRoyalePanelSettings.asset

   m_EditorClassIdentifier: 
   themeUss: {fileID: 11400000, guid: f567955c754d54a108d615cb51ccbf2f, type: 2}
   m_TargetTexture: {fileID: 0}
-  m_ScaleMode: 1
+  m_ScaleMode: 0
   m_Scale: 1
   m_ReferenceDpi: 128
   m_FallbackDpi: 96
   m_SortingOrder: 0
+  m_ClearDepthStencil: 1
+  m_ClearColor: 0
+  m_ColorClearValue: {r: 0, g: 0, b: 0, a: 0}
+  m_DynamicAtlasSettings:
+    m_MinAtlasSize: 64
+    m_MaxAtlasSize: 4096
+    m_MaxSubTextureSize: 64
+    m_ActiveFilters: 31
+  textSettings: {fileID: 11400000, guid: fb48f3b3eecb047e88a6667306380d19, type: 2}

Packages/manifest.json

     "com.unity.textmeshpro": "3.0.1",
     "com.unity.timeline": "1.2.6",
     "com.unity.ugui": "1.0.0",
-    "com.unity.ui": "1.0.0-preview.11",
+    "com.unity.ui": "1.0.0-preview.12",
     "com.unity.ui.builder": "1.0.0-preview.9",
     "com.unity.vectorgraphics": "2.0.0-preview.12",
     "com.unity.modules.ai": "1.0.0",

Packages/packages-lock.json

       }
     },
     "com.unity.ui": {
-      "version": "1.0.0-preview.11",
+      "version": "1.0.0-preview.12",
       "depth": 0,
       "source": "registry",
       "dependencies": {