So, I have seen many plugins use multi-slug to check updates and retrieve it. E.g. it have a button which redirects
basename($_SERVER['REQUEST_URI']) which is equal to
and I think something like if statement with isset() and $_GET it retrieves updates (maybe with json file available in web) then it states that update is available.
add_menu_page or add_submenu_page doesn't have any multi-slug option and retrieving $_GET option. So how we will make double slug and check for it that it is isset and true or not.
The main problem I face is I cannot retrieve $_GET as i'm not making slug from admin.php, instead I'm making it from my own plugin.
I'm intermediate in wordpress (neither new nor professional).
Note: sorry for bad english