Use the text-direction-aware start/end variants instead.
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1495>
<child>
<object class="GtkBox">
<property name="visible">True</property>
- <property name="margin-left">100</property>
- <property name="margin-right">100</property>
+ <property name="margin-start">100</property>
+ <property name="margin-end">100</property>
<property name="margin-top">100</property>
<property name="margin-bottom">60</property>
<property name="orientation">vertical</property>