Getting a deprecation warning in WP 4.3

So on my site, I’m getting this:

Notice: wp_htmledit_pre is deprecated since version 4.3! Use format_for_editor() instead. in /var/www/danbailey.net/public_html/wp-includes/functions.php on line 3406

Site, obviously, is https://www.danbailey.net. Error shows up at the bottom of every page, even those not using the [ref] shortcodes.

Any chance a fix will be forthcoming?

https://www.ads-software.com/plugins/simple-footnotes/