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filter is not described

signup_get_available_languages filter-hook . WP 4.4.0

Filters the list of available languages for front-end site signups.

Passing an empty array to this hook will disable output of the setting on the signup form, and the default language will be used when creating the site.

Languages not already installed will be stripped.

Usage

add_filter( 'signup_get_available_languages', 'filter_function_name_8651' );
function filter_function_name_8651( $available_languages ){
	// filter...

	return $available_languages;
}
$available_languages(array)
Available languages.

Where the hook is called

signup_get_available_languages()
signup_get_available_languages
wp-signup.php 800
$languages = (array) apply_filters( 'signup_get_available_languages', get_available_languages() );

Where the hook is used (in WP core)

Does not used.