diff --git a/emacs/notmuch-lib.el b/emacs/notmuch-lib.el
index 6fc71cc7..1cc7e9c4 100644
--- a/emacs/notmuch-lib.el
+++ b/emacs/notmuch-lib.el
@@ -1037,6 +1037,14 @@ region if the region is active, or both `point' otherwise."
   'notmuch-interactive-region
   "notmuch 0.29")
 
+(defun notmuch--inline-override-types ()
+  "Override mm-inline-override-types to stop application/*
+parts from being displayed unless the user has customized
+it themselves."
+  (if (equal mm-inline-override-types
+	     (eval (car (get 'mm-inline-override-types 'standard-value))))
+      (cons "application/.*" mm-inline-override-types)
+    mm-inline-override-types))
 ;;; _
 
 (provide 'notmuch-lib)
diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el
index 7c1f02c9..69f6c845 100644
--- a/emacs/notmuch-show.el
+++ b/emacs/notmuch-show.el
@@ -1264,14 +1264,8 @@ matched."
   (let ((buffer-name (generate-new-buffer-name
 		      (or buffer-name
 			  (concat "*notmuch-" thread-id "*"))))
-	;; We override mm-inline-override-types to stop application/*
-	;; parts from being displayed unless the user has customized
-	;; it themselves.
-	(mm-inline-override-types
-	 (if (equal mm-inline-override-types
-		    (eval (car (get 'mm-inline-override-types 'standard-value))))
-	     (cons "application/*" mm-inline-override-types)
-	   mm-inline-override-types)))
+	(mm-inline-override-types (notmuch--inline-override-types)))
+
     (pop-to-buffer-same-window (get-buffer-create buffer-name))
     ;; No need to track undo information for this buffer.
     (setq buffer-undo-list t)