Thank you for the update, however when the plugin is active it causes layout errors with my templates and also the standard WP menu.
I think it is this this CSS that is causing the error:-
*:before, *:after {
box-sizing: border-box;
}
It is being pulled in from:-
https://maxcdn.bootstrapcdn.com/bootstrap/3.3.1/css/bootstrap.min.css?ver=1.1
I have not had a look through your code yet, but as it is fine with your plugin deactivated, I guess it is your plugin that is calling in the file?