Check whether the plugin is active by checking the active_plugins list.

Signature

is_plugin_active( $plugin )
plugin
 (string) Base plugin path from plugins directory.

Return

(boolean) True, if in the active plugins list. False, not in the list.

Source

function is_plugin_active( $plugin ) {
	return in_array( $plugin, (array) get_option( 'active_plugins', array() ) ) || is_plugin_active_for_network( $plugin );
}
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