WordPress at a glance
action is not described

manage_themes_custom_column action-hook . WP 3.1.0

Fires inside each custom column of the Multisite themes list table.

Usage

add_action( 'manage_themes_custom_column', 'action_function_name_2903', 10, 3 );
function action_function_name_2903( $column_name, $stylesheet, $theme ){
	// action...
}
$column_name(string)
Name of the column.
$stylesheet(string)
Directory name of the theme.
$theme(WP_Theme)
Current WP_Theme object.

Where the hook is called

WP_MS_Themes_List_Table::column_default()
wp-admin/includes/class-wp-ms-themes-list-table.php 592
do_action( 'manage_themes_custom_column', $column_name, $stylesheet, $theme );

Where the hook is used (in WP core)

Does not used.