I uninstalled and deleted the plugin. After that it started complaining about missing string
Notice: Invalid get_string() identifier: 'my_purchases' or component 'enrol_cart'. Perhaps you are missing $string['my_purchases'] = ''; in /lang/en/enrol_cart.php?
line 356 of /lib/classes/string_manager_standard.php: call to debugging()
line 7413 of /lib/moodlelib.php: call to core_string_manager_standard->get_string()
line 742 of /user/lib.php: call to get_string()
line 890 of /user/lib.php: call to user_convert_text_to_menu_items()
line 113 of /theme/boost_magnific/classes/navigation/primary.php: call to user_get_user_navigation_info()
line 70 of /theme/boost_magnific/classes/navigation/primary.php: call to theme_boost_magnific\navigation\primary->get_user_menu()
line 87 of /theme/boost_magnific/layout/drawers.php: call to theme_boost_magnific\navigation\primary->export_for_template()
line 1477 of /lib/outputrenderers.php: call to include()
line 1403 of /lib/outputrenderers.php: call to core_renderer->render_page_layout()
line 547 of /lib/outputrenderers.php: call to core_renderer->header()
line 346 of /admin/renderer.php: call to plugin_renderer_base->__call()
line 217 of /admin/plugins.php: call to core_admin_renderer->plugin_management_page()
in lib/weblib.php on line 3428
I uninstalled and deleted the plugin. After that it started complaining about missing string