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Changes between Initial Version and Version 1 of Ticket #35251

initial	v1
1	1	The `networks` cache group is currently being prefixed with a blog ID, making it a repeated cache miss and duplicating cached data when using multiple networks and querying for them between dashboards.
2	2
3		The backstory goes that WordPress 4.4 introduced the `WP_Network` class (see: #31985) and with it came a simple new method for getting a network, aptly titled `get_instance()`. This method is used in `ms-settings.php` and `ms-load.php` in place of some previously duplicated and uncached code, and is used to retrieve a network's details from the ~~databas~~e. That query is wrapped in a new cache check with a new `networks` cache group, but this group was never added to the global cache groups array.
	3	The backstory goes that WordPress 4.4 introduced the `WP_Network` class (see: #31985) and with it came a simple new method for getting a network, aptly titled `get_instance()`. This method is used in `ms-settings.php` and `ms-load.php` in place of some previously duplicated and uncached code, and is used to retrieve a network's details from the `wp_sites` database table. That query is wrapped in a new cache check with a new `networks` cache group, but this group was never added to the global cache groups array.
4	4
5	5	It's not a regression, but it could be slipped into 4.4.1 as it was an unintentional oversight that could cause cache corruption in multi-network setups.