don't show external edit action if extension is pdf or jpg

src/collective/dms/basecontent/browser/column.py

@@ -1,3 +1,4 @@
+import os.path
 import Missing
 from AccessControl import getSecurityManager
 from Products.CMFCore.utils import getToolByName
@@ -156,6 +157,13 @@ class ExternalEditColumn(IconColumn, LinkColumn):
         if not sm.checkPermission('Modify portal content', obj):
             return False
 
+        if obj.file is None:
+            return False
+
+        ext = os.path.splitext(obj.file.filename)[-1].lower()
+        if ext in (u'.pdf', u'.jpg', '.jpeg'):
+            return False
+
         if not obj.restrictedTraverse('@@externalEditorEnabled').available():
             return False