I've been waiting years for them to fix this, I guess I have to make a formal request.
Akismet is the only part of WordPress that still relies on browser referer to redirect, specifically the "Check for Spam" button, ie.
This fails in many browsers because of personal security firewalls/antivirus packages that block browser referer.
Around line 692 in
wp_redirect( $_SERVER['HTTP_REFERER'] );
Please either pass the old url or return them to the only logical place the function call could have been from,
/wp-admin/edit-comments.php - and/or first check if the referer is valid or even exists.