Repository: khronosgroup/gltf-blender-io
Issue: Remember Export Settings - Data>Lighting>Lighting mode is not saved. 

When exporting a model to GLTF or GLB, the lighting mode can be switched between Unitless, Raw, or Standard. 
This setting is not saved on export correctly; where while still using the same open instance of blender it will retain the setting, but saving and re-opening the blender instance will remove the saved selection. This is fine for small projects, but working with various GLB projects daily makes it more of an issue.

Steps to reproduce the behavior:
1. In a new instance of blender, or opening an old blend file, export to GLB and apply a variety of settings. Change the lighting mode via Data>Lighting.
2. Export the GLB. 
3. Re-export the model again, see that the new lighting mode is still selected.
4. Save the blend file and quit.
5. Re-open the blend file, and export again. Observe that all settings chosen are still set, but the lighting mode is not.

With 'Remember Export Settings' enabled, all settings available to the users should be retained if the blend file is saved and re-opened. 

 - OS: [macOS]
 - Blender Version [3.5]



Changed files:
addons/io_scene_gltf2/__init__.py, addons/io_scene_gltf2/blender/imp/gltf2_blender_light.py

diff --git a/addons/io_scene_gltf2/__init__.py b/addons/io_scene_gltf2/__init__.py
index fd78e79d..528cd27d 100644
--- a/addons/io_scene_gltf2/__init__.py
+++ b/addons/io_scene_gltf2/__init__.py
@@ -117,7 +117,7 @@ def on_export_format_changed(self, context):
 class ConvertGLTF2_Base:
     """Base class containing options that should be exposed during both import and export."""
 
-    convert_lighting_mode: EnumProperty(
+    export_import_convert_lighting_mode: EnumProperty(
         name='Lighting Mode',
         items=(
             ('SPEC', 'Standard', 'Physically-based glTF lighting units (cd, lx, nt)'),
@@ -797,7 +797,7 @@ class ExportGLTF2_Base(ConvertGLTF2_Base):
             export_settings['gltf_morph_anim'] = False
 
         export_settings['gltf_lights'] = self.export_lights
-        export_settings['gltf_lighting_mode'] = self.convert_lighting_mode
+        export_settings['gltf_lighting_mode'] = self.export_import_convert_lighting_mode
 
         export_settings['gltf_binary'] = bytearray()
         export_settings['gltf_binaryfilename'] = (
@@ -1054,7 +1054,7 @@ class GLTF_PT_export_data_lighting(bpy.types.Panel):
         sfile = context.space_data
         operator = sfile.active_operator
 
-        layout.prop(operator, 'convert_lighting_mode')
+        layout.prop(operator, 'export_import_convert_lighting_mode')
 
 class GLTF_PT_export_data_shapekeys(bpy.types.Panel):
     bl_space_type = 'FILE_BROWSER'
@@ -1500,7 +1500,7 @@ class ImportGLTF2(Operator, ConvertGLTF2_Base, ImportHelper):
         layout.prop(self, 'import_shading')
         layout.prop(self, 'guess_original_bind_pose')
         layout.prop(self, 'bone_heuristic')
-        layout.prop(self, 'convert_lighting_mode')
+        layout.prop(self, 'export_import_convert_lighting_mode')
 
     def invoke(self, context, event):
         import sys
diff --git a/addons/io_scene_gltf2/blender/imp/gltf2_blender_light.py b/addons/io_scene_gltf2/blender/imp/gltf2_blender_light.py
index db7c44f1..b742afbf 100644
--- a/addons/io_scene_gltf2/blender/imp/gltf2_blender_light.py
+++ b/addons/io_scene_gltf2/blender/imp/gltf2_blender_light.py
@@ -57,27 +57,27 @@ class BlenderLight():
         sun = bpy.data.lights.new(name=pylight['name'], type="SUN")
 
         if 'intensity' in pylight.keys():
-            if gltf.import_settings['convert_lighting_mode'] == 'SPEC':
+            if gltf.import_settings['export_import_convert_lighting_mode'] == 'SPEC':
                 sun.energy = pylight['intensity'] / PBR_WATTS_TO_LUMENS
-            elif gltf.import_settings['convert_lighting_mode'] == 'COMPAT':
+            elif gltf.import_settings['export_import_convert_lighting_mode'] == 'COMPAT':
                 sun.energy = pylight['intensity']
-            elif gltf.import_settings['convert_lighting_mode'] == 'RAW':
+            elif gltf.import_settings['export_import_convert_lighting_mode'] == 'RAW':
                 sun.energy = pylight['intensity']
             else:
-                raise ValueError(gltf.import_settings['convert_lighting_mode'])
+                raise ValueError(gltf.import_settings['export_import_convert_lighting_mode'])
 
         return sun
 
     @staticmethod
     def _calc_energy_pointlike(gltf, pylight):
-        if gltf.import_settings['convert_lighting_mode'] == 'SPEC':
+        if gltf.import_settings['export_import_convert_lighting_mode'] == 'SPEC':
             return pylight['intensity'] / PBR_WATTS_TO_LUMENS * 4 * pi
-        elif gltf.import_settings['convert_lighting_mode'] == 'COMPAT':
+        elif gltf.import_settings['export_import_convert_lighting_mode'] == 'COMPAT':
             return pylight['intensity'] * 4 * pi
-        elif gltf.import_settings['convert_lighting_mode'] == 'RAW':
+        elif gltf.import_settings['export_import_convert_lighting_mode'] == 'RAW':
             return pylight['intensity']
         else:
-            raise ValueError(gltf.import_settings['convert_lighting_mode'])
+            raise ValueError(gltf.import_settings['export_import_convert_lighting_mode'])
 
     @staticmethod
     def create_point(gltf, light_id):