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function is not described

is_plugin_active_for_network() WP 3.0.0

Determines whether the plugin is active for the entire network.

Only plugins installed in the plugins/ folder can be active.

Plugins in the mu-plugins/ folder can't be "activated," so this function will return false for those plugins.

For more information on this and similar theme functions, check out the Conditional Tags article in the Theme Developer Handbook.

No Hooks.

Return

true/false. True if active for the network, otherwise false.

Usage

is_plugin_active_for_network( $plugin );
$plugin(string) (required)
Path to the plugin file relative to the plugins directory.

Changelog

Since 3.0.0 Introduced.

Code of is plugin active for network: wp-admin/includes/plugin.php WP 5.2.3

<?php
function is_plugin_active_for_network( $plugin ) {
	if ( ! is_multisite() ) {
		return false;
	}

	$plugins = get_site_option( 'active_sitewide_plugins' );
	if ( isset( $plugins[ $plugin ] ) ) {
		return true;
	}

	return false;
}