diff --git a/gajim/dialogs.py b/gajim/dialogs.py
index 804ae8840..9a045ad5b 100644
--- a/gajim/dialogs.py
+++ b/gajim/dialogs.py
@@ -2364,7 +2364,8 @@ class SubscriptionRequestWindow(Gtk.ApplicationWindow):
         self.destroy()
 
 class JoinGroupchatWindow(Gtk.ApplicationWindow):
-    def __init__(self, account, room_jid, password=None, automatic=None):
+    def __init__(self, account, room_jid, password=None, automatic=None,
+    transient_for=None):
         Gtk.ApplicationWindow.__init__(self)
         self.set_name('JoinGroupchat')
         self.set_application(app.app)
@@ -2372,6 +2373,8 @@ class JoinGroupchatWindow(Gtk.ApplicationWindow):
         self.set_resizable(False)
         self.set_position(Gtk.WindowPosition.CENTER)
         self.set_title(_('Join Groupchat'))
+        if transient_for:
+            self.set_transient_for(transient_for)
 
         self.automatic = automatic
         self.password = password
diff --git a/gajim/disco.py b/gajim/disco.py
index 0a807ed89..48f1ff827 100644
--- a/gajim/disco.py
+++ b/gajim/disco.py
@@ -1399,7 +1399,8 @@ class ToplevelAgentBrowser(AgentBrowser):
         if not iter_:
             return
         service = model[iter_][0]
-        app.interface.join_gc_minimal(self.account, service)
+        app.interface.join_gc_minimal(self.account, service,
+            transient_for=self.window.window)
 
     def update_actions(self):
         if self.execute_button:
diff --git a/gajim/gui_interface.py b/gajim/gui_interface.py
index d99eb7ff3..ed7fc2990 100644
--- a/gajim/gui_interface.py
+++ b/gajim/gui_interface.py
@@ -1818,7 +1818,8 @@ class Interface:
                 ctrl.scroll_to_end()
 
 
-    def join_gc_minimal(self, account, room_jid, password=None):
+    def join_gc_minimal(self, account, room_jid, password=None,
+    transient_for=None):
         if account is not None:
             if app.in_groupchat(account, room_jid):
                 # If we already in the groupchat, join_gc_room will bring
@@ -1855,7 +1856,8 @@ class Interface:
                 dialogs.ErrorDialog(_('JID is not a Groupchat'),
                                     transient_for=app.app.get_active_window())
                 return
-            dialogs.JoinGroupchatWindow(account, room_jid, password=password)
+            dialogs.JoinGroupchatWindow(account, room_jid, password=password,
+                transient_for=transient_for)
 
         disco_account = connected_accounts[0] if account is None else account
         app.connections[disco_account].discoverMUC(