WordPress at a glance
function is not described

get_user_setting() WP 2.7.0

Retrieve user interface setting value based on setting name.

No Hooks.

Return

Mixed. the last saved user setting or the default value/false if it doesn't exist.

Usage

get_user_setting( $name, $default );
$name(string) (required)
The name of the setting.
$default(string)
Optional default value to return when $name is not set.
Default: false

Code of get user setting: wp-includes/option.php WP 5.2.2

<?php
function get_user_setting( $name, $default = false ) {
	$all_user_settings = get_all_user_settings();

	return isset( $all_user_settings[ $name ] ) ? $all_user_settings[ $name ] : $default;
}