To keep Atahualpa compatible with PHP 8.1 you should change the following:
in functions/bfa_ata_custom_comments.php to remove some notice level errors:
old: $comment = get_comment($comment_id);
Code:
$comment = get_comment($comment_id ?? 0);
To remove warnings and in some cases a crash in functions.php
Remove the lines 858 to 863 - Internet Explorer 6 is long dead and there are some problems with this function. I don't think it would work anyhow so no reason in fixing it:
Code:
if ($bfa_ata['pngfix_selectors'] != "" AND $isIE6 = TRUE)
{
wp_register_script('ddroundies', $templateURI . '/js/DD_roundies.js', false, '0.0.2a' );
wp_enqueue_script('ddroundies');
add_action('wp_head', 'bfa_ddroundiesHead');
}
As well as don't forget to remove line 107 (the closing ampersand) from js.php from version 3.7.26
I attach the 3 files below (cannot attach full version due to file size attachement restrictions):