{{ self.title }}

All tags on this page are called with use_specific=3.

You can also use use_specific=USE_SPECIFIC_ALWAYS, as that is present in the context and has the same value ({{ USE_SPECIFIC_ALWAYS }})

{% section_menu max_levels=2 use_specific=3 template="menus/custom_section_menu.html" sub_menu_template="menus/custom_sub_menu.html" %}