small fix

src/window.cmb

@@ -63,7 +63,6 @@
 	(6,9,"GtkWidget","hexpand","True",None,None,None,None,None,None,None,None,None),
 	(6,9,"GtkWidget","width-request","100",None,None,None,None,None,None,None,None,None),
 	(6,10,"GtkOrientable","orientation","vertical",None,None,None,None,None,None,None,None,None),
-	(6,10,"GtkWidget","margin-bottom","5",None,None,None,None,None,None,None,None,None),
 	(6,11,"AdwPreferencesGroup","title","GTK",None,None,None,None,None,None,None,None,None),
 	(6,12,"AdwPreferencesRow","title","_Light",1,None,None,None,None,None,None,None,None),
 	(6,12,"AdwPreferencesRow","use-underline","True",None,None,None,None,None,None,None,None,None),

src/window.ui

 <?xml version='1.0' encoding='UTF-8'?>
-<!-- Created with Cambalache 0.91.1 -->
+<!-- Created with Cambalache 0.90.4 -->
 <interface>
   <!-- interface-name window.ui -->
   <requires lib="Adw" version="1.0"/>
@@ -59,7 +59,6 @@
                 </child>
                 <child>
                   <object class="GtkBox">
-                    <property name="margin-bottom">5</property>
                     <property name="orientation">vertical</property>
                     <child>
                       <object class="AdwPreferencesGroup">