--- thunderbird-91.4.1/mach.orig	2021-12-23 10:55:38.758897708 +0100
+++ thunderbird-91.4.1/mach	2021-12-23 10:55:46.712045948 +0100
@@ -124,6 +124,7 @@
 
 import os
 import sys
+import setuptools
 
 def load_mach(dir_path, mach_path):
     if sys.version_info < (3, 5):