Splash screen will be broken on SSL pages

The WordPress plugin is embedding
http://fightforthefuture.github.io/reset-the-net-widget/widget/rtn.js

Newer browsers prevent embedding non-SSL sources on SSL-encrypted pages. So by hard-coding “http://” the widget will break on any secured page.

A solution to this is to drop the “http://” and simply embed like so:
//fightforthefuture.github.io/reset-the-net-widget/widget/rtn.js

https://wordpress.org/plugins/reset-the-net-splash-screen/