How can I sort the categories alphabetically in the item post?
I have this for code

<?php ItemForm::category_select(null, osc_item_category_id(), __('Select a category', 'sigma')); ?>Is it sorted by code?
or add javascript
What is the method and if it is possible?
Thank you

@rooman
Categories should be sorted in order they are in backoffice.

Sorting the categories in the order in the back office is only
in the header.php
Homepage
What do I mean by adding an ad?
item post file 

Is there a solution for that? 

@rooman
If SQL is not natively using sorting, database one is used.
Solution could be to check ajax.php of theme (or Model file) and add your custom sorting here.