After adding the code above I will test, when I click on add listing appears the categories then select the category and then the page is blank only with the title “Select Category” does not display ad details.
Please try to re-save the child category (or the parent category of these child categories) of your selected category and check if the problem still exists.
Your solution worked, I will purchase the full package.
I did some thorough research here in the community and noticed that a feature many people are using in their projects is now outdated, but I would appreciate it if you could find a way to support it without the need to create code snippets.