diff --git a/src/calibre/gui2/__init__.py b/src/calibre/gui2/__init__.py
index 480b9e9581..a67dc74680 100644
--- a/src/calibre/gui2/__init__.py
+++ b/src/calibre/gui2/__init__.py
@@ -815,9 +815,12 @@ class FileIconProvider(QFileIconProvider):
 
     def key_from_ext(self, ext):
         key = ext if ext in self.icons else 'default'
-        if key == 'default' and ext.count('.') > 0:
+        if key == 'default' and '.' in ext:
             ext = ext.rpartition('.')[2]
             key = ext if ext in self.icons else 'default'
+        if key == 'default' and ext.startswith('original_'):
+            ext = ext.partition('_')[2]
+            key = ext if ext in self.icons else 'default'
         if key == 'default':
             key = ext
         return key