--- libportal-0.6/libportal/portal-gtk4.c.orig     2022-09-18 20:56:10.062136394 +0100                                                                        
+++ libportal-0.6/libportal/portal-gtk4.c  2022-09-18 20:59:44.879138215 +0100                                                                                
@@ -258,9 +258,13 @@                                                                                                                       
 xdp_portal_init (XdpPortal *portal)                                                                                                       
 {                                                                                                                                         
   int i;                                                                                                                                  
+  const gchar *dbus_connection_name;                                                                                                      
                                                                                                                                           
   portal->bus = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, NULL);                                                                          
-  portal->sender = g_strdup (g_dbus_connection_get_unique_name (portal->bus) + 1);                                                        
+  dbus_connection_name = portal->bus ? g_dbus_connection_get_unique_name (portal->bus) : NULL;                                            
+  if (!dbus_connection_name)                                                                                                              
+    dbus_connection_name = "_DBUS_NOT_PRESENT";                                                                                           
+  portal->sender = g_strdup (dbus_connection_name + 1);                                                                                   
   for (i = 0; portal->sender[i]; i++)                                                                                                     
     if (portal->sender[i] == '.')                                                                                                         
       portal->sender[i] = '_';