diff --git a/CHANGELOG.md b/CHANGELOG.md
index c520590..89810e3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,11 @@ Activate / deactivate layer opaticty according to prefix
 Activate / deactivate all masks using MA layers
 -->
 
+
+0.9.2
+
+- feat: add button to check if and which layers have masks
+
 0.9.1
 
 - change: stop reporting all use light disable on `check layer` (too many messages)
diff --git a/OP_setup_layers.py b/OP_setup_layers.py
index 6e2a64c..1922463 100644
--- a/OP_setup_layers.py
+++ b/OP_setup_layers.py
@@ -8,6 +8,8 @@ from . import fn
 import math
 import re
 
+## TODO : export json info to re-setup layers in AE automagically
+
 class GPEXP_OT_layers_state(bpy.types.Operator):
     bl_idname = "gp.layers_state"
     bl_label = "Set Layers State"
@@ -103,6 +105,7 @@ class GPEXP_OT_layers_state(bpy.types.Operator):
                 #         mlinvert = ' <>' if ml.invert else ''
                 #         print(f'{ml.info}{mlstate}{mlinvert}')
 
+
                 if l.opacity != 1:
                     # TODO Skip zeroed opacity ?
                     # check if there is an exclusion word
@@ -135,6 +138,13 @@ class GPEXP_OT_layers_state(bpy.types.Operator):
                         l.blend_mode = 'REGULAR'
                     used = True
 
+                if len(l.frames) == 1 and len(l.frames[0].strokes) == 0 and not l.hide:
+                    # probably used as separator
+                    l.hide = True
+                    mess = f'{l.info} : No frames. Hiding layer'
+                    print(mess)
+                    changes.append(mess)
+                    used = True
 
                 if used:
                     print()
@@ -315,10 +325,65 @@ class GPEXP_OT_auto_number_object(bpy.types.Operator):
 
         return {"FINISHED"}
 
+
+class GPEXP_OT_check_masks(bpy.types.Operator):
+    bl_idname = "gp.check_masks"
+    bl_label = "Check Masks"
+    bl_description = "Check and report all masked GP layers"
+    bl_options = {"REGISTER", "UNDO"}
+
+    @classmethod
+    def poll(cls, context):
+        return context.object and context.object.type == 'GPENCIL'
+
+    def execute(self, context):
+        # if self.all_objects:
+        #     pool = [o for o in context.scene.objects if o.type == 'GPENCIL']
+        # else:
+        #     pool = [o for o in context.selected_objects if o.type == 'GPENCIL']
+        changes = []
+        pool = [o for o in context.scene.objects if o.type == 'GPENCIL']
+        for o in pool:
+            for l in o.data.layers:
+                if l.use_mask_layer:
+                    obj_stat = f'{o.name} >>'
+                    if not obj_stat in changes:
+                        changes.append(obj_stat)
+                        print(obj_stat)
+                    
+                    hide_state = ' (hided)' if l.hide else ''
+                    text = f'  {l.info}{hide_state}:' # :masks: 
+                    changes.append(text)
+                    print(text)
+                    
+                    has_masks = False
+                    for ml in l.mask_layers:
+                        # 'hide', 'invert', 'name'
+                        h = ' hided' if ml.hide else ''
+                        i = ' (inverted)' if ml.invert else '' 
+                        text = f'   - {ml.name}{h}{i}'
+                        changes.append(text)
+                        print(text)
+                        has_masks = True
+
+                    if not has_masks:
+                        text = 'No masks!'
+                        changes.append(text)
+                        print(text)                        
+                    changes.append('')
+
+        if changes:
+            fn.show_message_box(_message=changes, _title="Masks Check Report", _icon='INFO')
+        else:
+            fn.show_message_box(_message='No Masks!', _title="Masks Check Report", _icon='INFO')
+
+        return {"FINISHED"}
+
 classes=(
 GPEXP_OT_layers_state,
 GPEXP_OT_lower_layers_name,
-GPEXP_OT_auto_number_object
+GPEXP_OT_auto_number_object,
+GPEXP_OT_check_masks,
 )
 
 def register(): 
diff --git a/__init__.py b/__init__.py
index e24677c..f9a06cd 100644
--- a/__init__.py
+++ b/__init__.py
@@ -2,7 +2,7 @@ bl_info = {
     "name": "GP Render",
     "description": "Organise export of gp layers through compositor output",
     "author": "Samuel Bernou",
-    "version": (0, 9, 1),
+    "version": (0, 9, 2),
     "blender": (2, 93, 0),
     "location": "View3D",
     "warning": "",
diff --git a/ui.py b/ui.py
index 2c00ee6..d159972 100644
--- a/ui.py
+++ b/ui.py
@@ -213,6 +213,7 @@ class GPEXP_PT_gp_dopesheet_ui(Panel):
         row.operator('gp.auto_number_object', icon='X', text='').delete = True
         col.operator('gp.layers_state', icon='CHECKMARK', text='Check layers')
         col.operator('gp.lower_layers_name', icon='SYNTAX_OFF', text='Rename Lowercase')
+        col.operator('gp.check_masks', icon='MOD_MASK', text='Has Masks')
         
         # row = layout.row()
         layout.prop(bpy.context.preferences.edit, 'use_anim_channel_group_colors')