WordPress at a glance
action is not described

customize_render_control action-hook . WP 3.4.0

Fires just before the current Customizer control is rendered.

Usage

add_action( 'customize_render_control', 'action_function_name_921' );
function action_function_name_921( $this ){
	// action...
}
$this(WP_Customize_Control)
WP_Customize_Control instance.

Where the hook is called

WP_Customize_Control::maybe_render()
wp-includes/class-wp-customize-control.php 398
do_action( 'customize_render_control', $this );

Where the hook is used (in WP core)

Does not used.