[Resolved] The menu is disabled under Appearance for Twenty Twenty-Four theme

Problem:
If you're experiencing issues with adding a language widget to the menu bar in the Twenty Twenty-Four theme because the menu is disabled under Appearance, we can help.
Solution:
1) The Twenty Twenty-Four theme does not support editing menus under Appearance -> Menus. Instead, you can edit the navigation template using the WordPress editor and add a language switcher block. We recommend following this guide: https://wpml.org/documentation/getting-started-guide/language-setup/language-switcher-options/#add-language-switcher-template.
2) Additionally, it appears that the WP memory limit needs to be increased for optimal performance with WPML. Although this is not directly related to your issue, increasing the memory limit can improve overall site performance. You can increase the memory limit by adding the following code to your wp-config.php file right before the /* That's all, stop editing! Happy publishing. */ line:

/* Memory Limit */<br />define('WP_MEMORY_LIMIT', '256M');<br />define('WP_MAX_MEMORY_LIMIT', '256M');

If this solution does not apply to your case, or if it seems outdated, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If you still need assistance, please open a new support ticket at WPML support forum.