Index: b/src/screenshot-dialog.c
===================================================================
--- a/src/screenshot-dialog.c
+++ b/src/screenshot-dialog.c
@@ -260,6 +260,8 @@
   if (!dialog->save_button)
   dialog->save_button = GTK_WIDGET (gtk_builder_get_object (ui, "save_button"));
   g_signal_connect (dialog->save_button, "clicked", G_CALLBACK (button_clicked), dialog);
+  gtk_widget_set_can_default (dialog->save_button, TRUE);
+  gtk_widget_grab_default (dialog->save_button);
   if (!dialog->copy_button)
   dialog->copy_button = GTK_WIDGET (gtk_builder_get_object (ui, "copy_button"));
   g_signal_connect (dialog->copy_button, "clicked", G_CALLBACK (button_clicked), dialog);
