--- inn-2.6.3/lib/newsuser.c.orig	2019-02-07 16:02:22.000000000 +0100
+++ inn-2.6.3/lib/newsuser.c	2020-11-07 18:31:54.357153294 +0100
@@ -100,6 +100,8 @@
         die ("must be run as %s group",
              innconf != NULL ? innconf->runasgroup : RUNASGROUP);
     }
+    const char *runasuser = innconf != NULL ? innconf->runasuser : RUNASUSER;
+    initgroups(runasuser, gid);
 }
 
 /*