fix delete view layer error in merge

CHANGELOG.md

@@ -17,6 +17,7 @@ Activate / deactivate all masks using MA layers
 1.3.5
 
 - added: button to exclude viewlayers and nodes by selection or by hided layers
+- fixed: `delete view layer` error in merge, when fusing multiple view layer
 
 1.3.4
 

fn.py

@@ -476,9 +476,11 @@ def merge_gplayer_viewlayers(ob=None, act=None, layers=None):
     if not act.viewlayer_render:
         return ({'ERROR'}, f'Active layer {act.info} has no viewlayer assigned')
 
-    # list layers and viewlayers
+    # List layers and viewlayers
     vls = [rd_scn.view_layers.get(l.viewlayer_render) for l in layers
         if l.viewlayer_render and l.viewlayer_render != act.viewlayer_render and rd_scn.view_layers.get(l.viewlayer_render)]
+    # Remove duplication
+    vls = list(set(vls)) 
 
     # Remove viewlayer related nodes
     remove_nodes_by_viewlayer(vls, rd_scn)
@@ -490,6 +492,8 @@ def merge_gplayer_viewlayers(ob=None, act=None, layers=None):
     ## Delete unused viewlayers ()
 
     used_vl_name = [n.layer for n in rd_scn.node_tree.nodes if n.type == 'R_LAYERS' and n.layer]
+    used_vl_name = list(set(used_vl_name))
+
     for vl in vls:
         # rd_scn.view_layers.remove(vl)
         if vl.name == 'exclude':