Bootstrap 4 collapsible sidebar, persistence on page reload

I would like to preface this with saying that english is not my mother tongue, if any of my explanations are vague or don't make sense, please let me know and I will attempt to make them clearer.

I'm playing around with collapsible sidebars (based on a tutorial by Bootstrapious) and I've cobbled together some js (based on this codepen) to save the current toggle state of the sidebar, to keep it persistent between reloads.

var sidebarState = window.localStorage.getItem('sidebarState');

windowWidth = $(window).width();

$(window).resize(function() {
  windowWidth = $(window).width();

    if(sidebarState){
        $('#sidebar').addClass('sidebar-collapsed').removeClass('sidebar-expanded'); 
    }
    else{
        $('#sidebar').addClass('sidebar-expanded').removeClass('sidebar-collapsed'); 
    }
});

$(function() {

    if (sidebarState == "collapsed"){
        $('#sidebar').addClass('sidebar-collapsed').removeClass('sidebar-expanded');
    }
    else{
        if(sidebarState){
        $('#sidebar').addClass('sidebar-collapsed').removeClass('sidebar-expanded'); 
        }
        else{
            $('#sidebar').addClass('sidebar-expanded').removeClass('sidebar-collapsed'); 
        }
    }

    $('#sidebarCollapse').on('click', function(){
        if ( !($('#sidebar').hasClass('sidebar-collapsed')) ) {
            $('#sidebar').addClass('sidebar-collapsed').removeClass('sidebar-expanded');
            window.localStorage.setItem('sidebarState', 'collapsed')
        }
        else{
            $('#sidebar').addClass('sidebar-expanded').removeClass('sidebar-collapsed');
            window.localStorage.removeItem('sidebarState')
        }
        return false;
    });
});

What can I do to hide the transition when the sidebar is collapsed and then the page is reloaded? As it stands right now you'll see the transition from expanded to collapsed, and it makes for a very annoying experience. I tried removing the transition altogether from the stylesheet, but that doesn't make a huge difference. Any help will be greatly appreciated.

Link to codepen: https://codepen.io/anon/pen/eLjwpE