WordPress: Show current screen ID and Base in the admin footer, visible only on hover

wp-show-screen-id-in-admin-footer.php

<?php
/* Show current screen ID and Base in the bottom left of the dashboard footer. Hidden until you hover over it. Great for easily identifying the current screen during plugin development. */
function rs_display_screen_id_in_footer( $text ) {
	if ( !function_exists('get_current_screen') ) return;
	
	$screen = get_current_screen();
	
	return $text . ' <span style="opacity: 0;" onmouseover="jQuery(this).css(\'opacity\', 1);" onmouseout="jQuery(this).css(\'opacity\', 0);">screen id: '. $screen->id . '; base: ' . $screen->base . '</span>';
}
add_action( 'admin_footer_text', 'rs_display_screen_id_in_footer', 20 );