Side Menu Items Custom Links

Hi phoenixobia,

Thank you for your feedback.

add a custom Tab with custom URL

Sorry, I don’t know it custom Tab and custom URL.
Could you please tell me the details?(screenshot, movie, etc…)

And, If custom URL is mean to external URL, sorry you will can’t add.

One of my tabs doesn’t work after I use this and it gives me a 404 page.

Could you please tell me did you have error if you settings before customize state?
i.e.) I think this error is menu parent slug is different.

Thanks,
gqevu6bsiz

Thank you for your reply.
Sorry it not can to add the Tabs/Custom Links.
But you will be able to customize after you will create the custom admin screen/menu.
e.g.)
Document: https://codex.ww.wp.xz.cn/Administration_Menus

add_action( 'admin_menu', 'my_plugin_menu' );
function my_plugin_menu() {
	add_menu_page( 'Example Title', 'Example Title', 'edit_posts', 'example_title', 'example_func' );
}
function example_func()
{
	echo 'Example Contents <br />';
	echo 'URL = ' . $_SERVER['REQUEST_URI'];
}

Screenshot of settings: http://gqevu6bsiz.chicappa.jp/?attachment_id=1686
Screenshot of customized: http://gqevu6bsiz.chicappa.jp/?attachment_id=1687

You mean this custom screen/menu?

Thanks,
gqevu6bsiz