new WP version doesnt support 2.4.1

Hi,
new WP version doesnt support 2.4.1. The Alert syas:

The method for WP_Widget is outdated since version 4.3.0 ! use instead

__construct()
. in …/wp-includes/functions.php on line 3457

is there any new version on the way ??? or the problem is something else??

Thanx
GM

https://wordpress.org/plugins/likebtn-like-button/