commit 931112aec0ba5a626327d8cb490b0b86e4c0b55c
Author: Carlos Garnacho <carlosg@gnome.org>
Date:   Thu Sep 21 13:23:00 2023 +0200

    application: Handle TeclaModel constructor possibly returning NULL
    
    This might be the case if an unknown keymap name is passed as a
    commandline argument. We ATM just show a window with empty keys,
    so there's room for improvement in the future (e.g. state that
    the keymap does not exist).

diff -Nura tecla-45.0/src/tecla-application.c tecla-45.0_new/src/tecla-application.c
--- tecla-45.0/src/tecla-application.c	2023-09-17 01:02:57.000000000 +0800
+++ tecla-45.0_new/src/tecla-application.c	2024-03-31 16:28:22.603133598 +0800
@@ -375,11 +375,14 @@
 	if (tecla_app->layout) {
 		tecla_app->main_model =
 			tecla_model_new_from_layout_name (tecla_app->layout);
-		connect_model (tecla_app->main_window,
-			       tecla_app->main_view,
-			       tecla_app->main_model);
-		g_clear_pointer (&tecla_app->layout, g_free);
-		update_title (tecla_app->main_window, tecla_app->main_model);
+
+                if (tecla_app->main_model) {
+                        connect_model (tecla_app->main_window,
+                                       tecla_app->main_view,
+                                       tecla_app->main_model);
+                        g_clear_pointer (&tecla_app->layout, g_free);
+                        update_title (tecla_app->main_window, tecla_app->main_model);
+                }
 	}
 
 	gtk_window_present (tecla_app->main_window);