get_subdirectory_reserved_name bypass on mutlisite

[knightrider123]

By default on Multisite installation, you cannot have subsite(subdirectory) with name /blog/ due to: ​https://developer.wordpress.org/reference/functions/get_subdirectory_reserved_names/ as this tigger an error when you try to create such subsite:

The following words are reserved for use by WordPress functions and cannot be used as site names: page, comments, blog, files, feed, wp-admin, wp-content, wp-includes, wp-json, embed

But you can bypass that by creating subsite /aaa/ and edit name later on in network. I wonder is that a bug, and if so will it cause any issues using such subsites slug?

The only one I have found so far is that if on main site you will have /blog/ page slug, after re-save slug will get the number at the end.

Also, if you can bypass that, maybe it should be removed from reserved list?

Apart from /blog/ slug I was able to replicate that for /comments/ using same bypass.

I could not find any information in that matter.

Thank you

[realloc]

I wouldn’t consider this a bug.

The functionality works as follows: A user cannot add a new site with the name “blog”. However, as a network admin, you have the ability to override this. Additionally, as a developer, you can override it using the subdirectory_reserved_names filter.

You can find more details in the section "User Contributed Notes" of the page that you mentioned:
​https://developer.wordpress.org/reference/functions/get_subdirectory_reserved_names/#user-contributed-notes