Enable SSS in the player

Assets/ScriptableRenderPipeline/HDRenderPipeline/HDRenderPipeline.cs

             }
 
             // Broadcast SSS parameters to all shaders.
+            Shader.SetGlobalInt("_EnableSSS", globalDebugSettings.renderingDebugSettings.enableSSS ? 1 : 0);
-
-            if (globalDebugSettings.renderingDebugSettings.enableSSS)
-            {
-                cmd.EnableShaderKeyword("_SUBSURFACE_SCATTERING");
-            }
-            else
-            {
-                cmd.DisableShaderKeyword("_SUBSURFACE_SCATTERING");
-            }
 
             renderContext.ExecuteCommandBuffer(cmd);
             cmd.Dispose();

Assets/ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/Lit.hlsl

 // SSS parameters
 #define SSS_N_PROFILES 8
 #define SSS_UNIT_CONVERSION (1.0 / 300.0)                  // From meters to 1/3 centimeters
+uint   _EnableSSS;                                         // Globally toggles subsurface scattering on/off
 uint   _TransmissionFlags;                                 // 1 bit/profile; 0 = inf. thick, 1 = supports transmission
 uint   _TexturingModeFlags;                                // 1 bit/profile; 0 = PreAndPostScatter, 1 = PostScatter
 float  _ThicknessRemaps[SSS_N_PROFILES][2];                // Remap: 0 = start, 1 = end - start

Assets/ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/Lit.shader

     #pragma shader_feature _DETAIL_MAP
     #pragma shader_feature _SUBSURFACE_RADIUS_MAP
     #pragma shader_feature _THICKNESS_MAP
-    #pragma shader_feature _SUBSURFACE_SCATTERING
     #pragma shader_feature _VERTEX_WIND
 
     #pragma multi_compile LIGHTMAP_OFF LIGHTMAP_ON

Assets/ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/LitDataInternal.hlsl

     // This part of the code is not used in case of layered shader but we keep the same macro system for simplicity
 #if !defined(LAYERED_LIT_SHADER)
 
-#ifdef _SUBSURFACE_SCATTERING
-    surfaceData.materialId = _MaterialID;
-#else
-    surfaceData.materialId = (_MaterialID == MATERIALID_LIT_SSS) ? 0 : _MaterialID;
-#endif
+    surfaceData.materialId = (_EnableSSS || _MaterialID != MATERIALID_LIT_SSS) ? _MaterialID : MATERIALID_LIT_STANDARD;
 
     // TODO: think about using BC5
 #ifdef _TANGENTMAP

Assets/ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/LitTessellation.shader

     #pragma shader_feature _DETAIL_MAP
     #pragma shader_feature _SUBSURFACE_RADIUS_MAP
     #pragma shader_feature _THICKNESS_MAP
-    #pragma shader_feature _SUBSURFACE_SCATTERING
     #pragma shader_feature _VERTEX_WIND
 
     #pragma multi_compile LIGHTMAP_OFF LIGHTMAP_ON