diff --git a/CHANGELOG.md b/CHANGELOG.md
index d88ed80..d2d7d6d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,10 @@ Activate / deactivate layer opacity according to prefix
 Activate / deactivate all masks using MA layers
 -->
 
+1.8.11
+
+- fixed: cleaning materials duplication checked against name without checking material GP type
+
 1.8.10
 
 - fixed: node not deleted after a merge using (compo scene not referenced correctly to point node_trees)
diff --git a/__init__.py b/__init__.py
index d91f8d2..ad14c40 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": (1, 8, 10),
+    "version": (1, 8, 11),
     "blender": (3, 0, 0),
     "location": "View3D",
     "warning": "",
diff --git a/fn.py b/fn.py
index 9f1598c..9200689 100644
--- a/fn.py
+++ b/fn.py
@@ -1855,6 +1855,9 @@ def clean_mats_duplication(ob, skip_different_materials=True):
         basemat = bpy.data.materials.get(match.group(1))
         if not basemat:
             continue
+        if not basemat.is_grease_pencil:
+            ## Skip material with matching "stem" but not being GP material
+            continue
         diff = different_gp_mat(mat, basemat)
         if diff:
             print(f'! {ob.name} : {diff}')