In fact, hierarchical subcategory files are always set by default in wordpress.
If you have a "good permalinks" structure selected in> permalinks settings, for example /%postname% , then the URLs of the category pages and subcategories should have a default value: yourdomain.com/category-base/category/sub-category/sub-sub-category
I ran into a similar issue with a recent WP project, BUT I used a plugin called WP No Base Permalink to get rid of my category and base slug tags in my permalinks. When I turned off the plugin, the category hierarchy suddenly returned to my permalinks in the archive (fortunately, this project was still under development, otherwise I would have 404 main problems).
I have not yet found / tested another plugin to eliminate the basic slug-systems of category / tags, which will also save the hierarchy in the URLs of the sub / category archive, but it turns out that I do not need this functionality for my current project.
Instead, I use the basic slugs blog-articles and blog-tags for standard categories and tags to establish blog taxonomies, among other taxonomies. Then I use the Types plugin to create a custom post type and custom taxonomies for this post type. The Types plugin has an option in the advanced settings for setting hierarchical taxonomic URLs true or false when creating a custom taxonomy.
Finally, I found a plugin called Remove Taxonomy Base Slug , which effectively excludes the default taxonomy term from the base pool of taxonomy archive URLs. And this, fortunately, does not interfere with the sub / category hierarchical attributes, or base bullets for standard tags and categories.
So my blog categories / tags are as follows:
yourdomain.com/blog-articles/category/sub-category/ or yourdomain.com/blog-tags/tag/
And my custom categories / message type tags look like this:
yourdomain.com/category/sub-category/ or yourdomain.com/tag/
Phew!
Hope this helps!
user2655393
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