diff --git a/src/Umbraco.Core/WebAssets/IRuntimeMinifier.cs b/src/Umbraco.Core/WebAssets/IRuntimeMinifier.cs
index 03f6b179ff..2b68a2f4ec 100644
--- a/src/Umbraco.Core/WebAssets/IRuntimeMinifier.cs
+++ b/src/Umbraco.Core/WebAssets/IRuntimeMinifier.cs
@@ -34,7 +34,7 @@ namespace Umbraco.Core.WebAssets
         /// <returns>
         /// An html encoded string
         /// </returns>
-        string RenderCssHere(string bundleName);
+        Task<string> RenderCssHereAsync(string bundleName);
 
         /// <summary>
         /// Creates a JS bundle
@@ -56,7 +56,7 @@ namespace Umbraco.Core.WebAssets
         /// <returns>
         /// An html encoded string
         /// </returns>
-        string RenderJsHere(string bundleName);
+        Task<string> RenderJsHereAsync(string bundleName);
 
         /// <summary>
         /// Returns the asset paths for the bundle name
diff --git a/src/Umbraco.Web.BackOffice/ActionResults/JsonNetResult.cs b/src/Umbraco.Web.BackOffice/ActionResults/JsonNetResult.cs
deleted file mode 100644
index db5c7a8510..0000000000
--- a/src/Umbraco.Web.BackOffice/ActionResults/JsonNetResult.cs
+++ /dev/null
@@ -1,52 +0,0 @@
-using System;
-using System.IO;
-using System.Text;
-using System.Threading.Tasks;
-using Microsoft.AspNetCore.Mvc;
-using Newtonsoft.Json;
-
-namespace Umbraco.Web.BackOffice.ActionResults
-{
-    /// <summary>
-    /// Custom json result using newtonsoft json.net
-    /// </summary>
-    public class JsonNetResult : IActionResult
-    {
-        public Encoding ContentEncoding { get; set; }
-        public string ContentType { get; set; }
-        public object Data { get; set; }
-
-        public JsonSerializerSettings SerializerSettings { get; set; }
-        public Formatting Formatting { get; set; }
-
-        public JsonNetResult()
-        {
-            SerializerSettings = new JsonSerializerSettings();
-        }
-
-        public Task ExecuteResultAsync(ActionContext context)
-        {
-            if (context is null)
-                throw new ArgumentNullException(nameof(context));
-
-            var response = context.HttpContext.Response;
-
-            response.ContentType = string.IsNullOrEmpty(ContentType) == false
-                ? ContentType
-                : System.Net.Mime.MediaTypeNames.Application.Json;
-
-            if (!(ContentEncoding is null))
-                response.Headers.Add(Microsoft.Net.Http.Headers.HeaderNames.ContentEncoding, ContentEncoding.ToString());
-
-            if (!(Data is null))
-            {
-                using var bodyWriter = new StreamWriter(response.Body);
-                using var writer = new JsonTextWriter(bodyWriter) { Formatting = Formatting };
-                var serializer = JsonSerializer.Create(SerializerSettings);
-                serializer.Serialize(writer, Data);
-            }
-
-            return Task.CompletedTask;
-        }
-    }
-}
diff --git a/src/Umbraco.Web.BackOffice/Controllers/BackOfficeController.cs b/src/Umbraco.Web.BackOffice/Controllers/BackOfficeController.cs
index aecad8c4e4..e7e817f649 100644
--- a/src/Umbraco.Web.BackOffice/Controllers/BackOfficeController.cs
+++ b/src/Umbraco.Web.BackOffice/Controllers/BackOfficeController.cs
@@ -1,11 +1,11 @@
 using System;
+using System.Collections.Generic;
 using System.Globalization;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.AspNetCore.Mvc;
-using Newtonsoft.Json;
 using Umbraco.Core;
 using Umbraco.Core.BackOffice;
 using Umbraco.Core.Cache;
@@ -15,8 +15,6 @@ using Umbraco.Core.Hosting;
 using Umbraco.Core.Services;
 using Umbraco.Core.WebAssets;
 using Umbraco.Extensions;
-using Umbraco.Net;
-using Umbraco.Web.BackOffice.ActionResults;
 using Umbraco.Web.BackOffice.Filters;
 using Umbraco.Web.Common.ActionResults;
 using Umbraco.Web.Models;
@@ -93,7 +91,7 @@ namespace Umbraco.Web.BackOffice.Controllers
         /// <param name="culture"></param>
         /// <returns></returns>
         [HttpGet]
-        public JsonNetResult LocalizedText(string culture = null)
+        public Dictionary<string, Dictionary<string, string>> LocalizedText(string culture = null)
         {
             var securityHelper = _umbracoContextAccessor.GetRequiredUmbracoContext().Security;
             var isAuthenticated = securityHelper.IsAuthenticated();
@@ -125,14 +123,14 @@ namespace Umbraco.Web.BackOffice.Controllers
                 .ToDictionary(pv => pv.Key, pv =>
                     pv.ToDictionary(pve => pve.valueAlias, pve => pve.value));
 
-            return new JsonNetResult { Data = nestedDictionary, Formatting = Formatting.None };
+            return nestedDictionary;
         }
 
         [UmbracoAuthorize(Order = 0)]
         [HttpGet]
-        public JsonNetResult GetGridConfig()
+        public IEnumerable<IGridEditorConfig> GetGridConfig()
         {
-            return new JsonNetResult { Data = _gridConfig.EditorsConfig.Editors, Formatting = Formatting.None };
+            return _gridConfig.EditorsConfig.Editors;
         }
 
         /// <summary>
@@ -156,7 +154,7 @@ namespace Umbraco.Web.BackOffice.Controllers
         }
 
         [HttpGet]
-        public async Task<ActionResult> ValidatePasswordResetCode([Bind(Prefix = "u")]int userId, [Bind(Prefix = "r")]string resetCode)
+        public async Task<IActionResult> ValidatePasswordResetCode([Bind(Prefix = "u")]int userId, [Bind(Prefix = "r")]string resetCode)
         {
             var user = await _userManager.FindByIdAsync(userId.ToString());
             if (user != null)
@@ -180,9 +178,9 @@ namespace Umbraco.Web.BackOffice.Controllers
         /// otherwise process the external login info.
         /// </summary>
         /// <returns></returns>
-        private async Task<ActionResult> RenderDefaultOrProcessExternalLoginAsync(
-            Func<ActionResult> defaultResponse,
-            Func<ActionResult> externalSignInResponse)
+        private async Task<IActionResult> RenderDefaultOrProcessExternalLoginAsync(
+            Func<IActionResult> defaultResponse,
+            Func<IActionResult> externalSignInResponse)
         {
             if (defaultResponse is null) throw new ArgumentNullException(nameof(defaultResponse));
             if (externalSignInResponse is null) throw new ArgumentNullException(nameof(externalSignInResponse));
@@ -213,7 +211,7 @@ namespace Umbraco.Web.BackOffice.Controllers
         // Used for XSRF protection when adding external logins
         private const string XsrfKey = "XsrfId";
 
-        private ActionResult RedirectToLocal(string returnUrl)
+        private IActionResult RedirectToLocal(string returnUrl)
         {
             if (Url.IsLocalUrl(returnUrl))
             {
diff --git a/src/Umbraco.Web.BackOffice/Controllers/BackOfficeServerVariables.cs b/src/Umbraco.Web.BackOffice/Controllers/BackOfficeServerVariables.cs
index 051193c290..e97ee0d1e5 100644
--- a/src/Umbraco.Web.BackOffice/Controllers/BackOfficeServerVariables.cs
+++ b/src/Umbraco.Web.BackOffice/Controllers/BackOfficeServerVariables.cs
@@ -48,6 +48,7 @@ namespace Umbraco.Web.BackOffice.Controllers
             IGlobalSettings globalSettings,
             IUmbracoVersion umbracoVersion,
             IContentSettings contentSettings,
+            IHttpContextAccessor httpContextAccessor,
             //TreeCollection treeCollection, // TODO: If we need this we need to migrate trees
             IHostingEnvironment hostingEnvironment,
             IRuntimeSettings settings,
@@ -62,6 +63,7 @@ namespace Umbraco.Web.BackOffice.Controllers
             _globalSettings = globalSettings;
             _umbracoVersion = umbracoVersion;
             _contentSettings = contentSettings ?? throw new ArgumentNullException(nameof(contentSettings));
+            _httpContextAccessor = httpContextAccessor;
             //_treeCollection = treeCollection ?? throw new ArgumentNullException(nameof(treeCollection));
             _hostingEnvironment = hostingEnvironment;
             _settings = settings;
diff --git a/src/Umbraco.Web/HtmlHelperBackOfficeExtensions.cs b/src/Umbraco.Web.BackOffice/Extensions/HtmlHelperBackOfficeExtensions.cs
similarity index 66%
rename from src/Umbraco.Web/HtmlHelperBackOfficeExtensions.cs
rename to src/Umbraco.Web.BackOffice/Extensions/HtmlHelperBackOfficeExtensions.cs
index bf1ad35bec..894ab5f5f6 100644
--- a/src/Umbraco.Web/HtmlHelperBackOfficeExtensions.cs
+++ b/src/Umbraco.Web.BackOffice/Extensions/HtmlHelperBackOfficeExtensions.cs
@@ -1,36 +1,32 @@
-using System.Collections.Generic;
+using Microsoft.AspNetCore.Authentication;
+using Microsoft.AspNetCore.Html;
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Routing;
+using Newtonsoft.Json;
+using System.Collections.Generic;
 using System.Linq;
 using System.Text;
-using System.Web;
-using System.Web.Mvc;
-using Microsoft.Owin.Security;
-using Newtonsoft.Json;
+using System.Threading.Tasks;
+using Umbraco.Core;
 using Umbraco.Core.Configuration;
 using Umbraco.Core.Configuration.UmbracoSettings;
 using Umbraco.Core.Hosting;
-using Umbraco.Core.IO;
-using Umbraco.Core.Runtime;
 using Umbraco.Core.WebAssets;
-using Umbraco.Web.Composing;
-using Umbraco.Web.Editors;
+using Umbraco.Web.BackOffice.Controllers;
 using Umbraco.Web.Features;
 using Umbraco.Web.Models;
-using Umbraco.Web.Security;
-using Umbraco.Web.Trees;
+using Umbraco.Web.WebApi;
 using Umbraco.Web.WebAssets;
 
-namespace Umbraco.Web
+namespace Umbraco.Extensions
 {
-    /// <summary>
-    /// HtmlHelper extensions for the back office
-    /// </summary>
     public static class HtmlHelperBackOfficeExtensions
     {
         /// <summary>
         /// Outputs a script tag containing the bare minimum (non secure) server vars for use with the angular app
         /// </summary>
         /// <param name="html"></param>
-        /// <param name="uri"></param>
+        /// <param name="linkGenerator"></param>
         /// <param name="features"></param>
         /// <param name="globalSettings"></param>
         /// <param name="umbracoVersion"></param>
@@ -46,10 +42,9 @@ namespace Umbraco.Web
         /// These are the bare minimal server variables that are required for the application to start without being authenticated,
         /// we will load the rest of the server vars after the user is authenticated.
         /// </remarks>
-        public static IHtmlString BareMinimumServerVariablesScript(this HtmlHelper html, UrlHelper uri, UmbracoFeatures features, IGlobalSettings globalSettings, IUmbracoVersion umbracoVersion, IContentSettings contentSettings, TreeCollection treeCollection, IHostingEnvironment hostingEnvironment, IRuntimeSettings settings, ISecuritySettings securitySettings, IRuntimeMinifier runtimeMinifier)
+        public static async Task<IHtmlContent> BareMinimumServerVariablesScriptAsync(this IHtmlHelper html, BackOfficeServerVariables backOfficeServerVariables)
         {
-            var serverVars = new BackOfficeServerVariables(uri, Current.RuntimeState, features, globalSettings, umbracoVersion, contentSettings, treeCollection, hostingEnvironment, settings, securitySettings, runtimeMinifier);
-            var minVars = serverVars.BareMinimumServerVariables();
+            var minVars = await backOfficeServerVariables.BareMinimumServerVariablesAsync();
 
             var str = @"<script type=""text/javascript"">
                 var Umbraco = {};
@@ -66,15 +61,24 @@ namespace Umbraco.Web
         /// <param name="html"></param>
         /// <param name="externalLoginErrors"></param>
         /// <returns></returns>
-        public static IHtmlString AngularValueExternalLoginInfoScript(this HtmlHelper html, IEnumerable<string> externalLoginErrors)
+        public static async Task<IHtmlContent> AngularValueExternalLoginInfoScriptAsync(this IHtmlHelper html,
+            IAuthenticationSchemeProvider authenticationSchemeProvider,
+            IEnumerable<string> externalLoginErrors)
         {
-            var loginProviders = html.ViewContext.HttpContext.GetOwinContext().Authentication.GetExternalAuthenticationTypes()
-                .Where(p => p.Properties.ContainsKey("UmbracoBackOffice"))
+            var providers = await authenticationSchemeProvider.GetAllSchemesAsync();
+
+            var loginProviders = providers
+                // TODO: We need to filter only back office enabled schemes.
+                // Before we used to have a property bag to check, now we don't so need to investigate the easiest/best
+                // way to do this. We have the type so maybe we check for a marker interface, but maybe there's another way,
+                // just need to investigate.
+                //.Where(p => p.Properties.ContainsKey("UmbracoBackOffice"))
                 .Select(p => new
                 {
-                    authType = p.AuthenticationType,
-                    caption = p.Caption,
-                    properties = p.Properties
+                    authType = p.Name,
+                    caption = p.DisplayName,
+                    // TODO: See above, if we need this property bag in the vars then we'll need to figure something out
+                    //properties = p.Properties
                 })
                 .ToArray();
 
@@ -105,7 +109,7 @@ namespace Umbraco.Web
         /// <param name="html"></param>
         /// <param name="val"></param>
         /// <returns></returns>
-        public static IHtmlString AngularValueResetPasswordCodeInfoScript(this HtmlHelper html, object val)
+        public static IHtmlContent AngularValueResetPasswordCodeInfoScript(this IHtmlHelper html, object val)
         {
             var sb = new StringBuilder();
             sb.AppendLine();
@@ -132,9 +136,9 @@ namespace Umbraco.Web
             return html.Raw(sb.ToString());
         }
 
-        public static IHtmlString AngularValueTinyMceAssets(this HtmlHelper html, IRuntimeMinifier runtimeMinifier)
+        public static async Task<IHtmlContent> AngularValueTinyMceAssetsAsync(this IHtmlHelper html, IRuntimeMinifier runtimeMinifier)
         {
-            var files = runtimeMinifier.GetAssetPathsAsync(BackOfficeWebAssets.UmbracoTinyMceJsBundleName).GetAwaiter().GetResult();
+            var files = await runtimeMinifier.GetAssetPathsAsync(BackOfficeWebAssets.UmbracoTinyMceJsBundleName);
 
             var sb = new StringBuilder();
 
diff --git a/src/Umbraco.Web.Common/Extensions/UrlHelperExtensions.cs b/src/Umbraco.Web.Common/Extensions/UrlHelperExtensions.cs
index 3b64125053..8b1d41634d 100644
--- a/src/Umbraco.Web.Common/Extensions/UrlHelperExtensions.cs
+++ b/src/Umbraco.Web.Common/Extensions/UrlHelperExtensions.cs
@@ -6,6 +6,11 @@ using Umbraco.Core;
 using Umbraco.Web.Common.Controllers;
 using Umbraco.Web.WebApi;
 using Umbraco.Web.Common.Install;
+using Microsoft.AspNetCore.Routing;
+using Umbraco.Core.Hosting;
+using System.Globalization;
+using Umbraco.Core.Configuration;
+using Umbraco.Core.WebAssets;
 
 namespace Umbraco.Extensions
 {
@@ -13,6 +18,8 @@ namespace Umbraco.Extensions
     public static class UrlHelperExtensions
     {
 
+        
+
         /// <summary>
         /// Return the back office url if the back office is installed
         /// </summary>
@@ -175,5 +182,40 @@ namespace Umbraco.Extensions
             }
             return url.GetUmbracoApiService<T>(umbracoApiControllerTypeCollection, method.Name).TrimEnd(method.Name);
         }
+
+        /// <summary>
+        /// Return the Url for an action with a cache-busting hash appended
+        /// </summary>
+        /// <param name="url"></param>
+        /// <param name="actionName"></param>
+        /// <param name="controllerName"></param>
+        /// <param name="routeVals"></param>
+        /// <returns></returns>
+        public static string GetUrlWithCacheBust(this IUrlHelper url, string actionName, string controllerName, RouteValueDictionary routeVals,
+            IHostingEnvironment hostingEnvironment, IUmbracoVersion umbracoVersion, IRuntimeMinifier runtimeMinifier)
+        {
+            var applicationJs = url.Action(actionName, controllerName, routeVals);
+            applicationJs = applicationJs + "?umb__rnd=" + GetCacheBustHash(hostingEnvironment, umbracoVersion, runtimeMinifier);
+            return applicationJs;
+        }
+
+        /// <summary>
+        ///
+        /// </summary>
+        /// <returns></returns>
+        public static string GetCacheBustHash(IHostingEnvironment hostingEnvironment, IUmbracoVersion umbracoVersion, IRuntimeMinifier runtimeMinifier)
+        {
+            //make a hash of umbraco and client dependency version
+            //in case the user bypasses the installer and just bumps the web.config or client dependency config
+
+            //if in debug mode, always burst the cache
+            if (hostingEnvironment.IsDebugMode)
+            {
+                return DateTime.Now.Ticks.ToString(CultureInfo.InvariantCulture).GenerateHash();
+            }
+
+            var version = umbracoVersion.SemanticVersion.ToSemanticString();
+            return $"{version}.{runtimeMinifier.CacheBuster}".GenerateHash();
+        }
     }
 }
diff --git a/src/Umbraco.Web.Common/RuntimeMinification/SmidgeRuntimeMinifier.cs b/src/Umbraco.Web.Common/RuntimeMinification/SmidgeRuntimeMinifier.cs
index c4b9522099..a33ac6f966 100644
--- a/src/Umbraco.Web.Common/RuntimeMinification/SmidgeRuntimeMinifier.cs
+++ b/src/Umbraco.Web.Common/RuntimeMinification/SmidgeRuntimeMinifier.cs
@@ -65,7 +65,7 @@ namespace Umbraco.Web.Common.RuntimeMinification
             // affect this or vice versa.
         }
 
-        public string RenderCssHere(string bundleName) => _smidge.SmidgeHelper.CssHereAsync(bundleName, _hostingEnvironment.IsDebugMode).ToString();
+        public async Task<string> RenderCssHereAsync(string bundleName) => (await _smidge.SmidgeHelper.CssHereAsync(bundleName, _hostingEnvironment.IsDebugMode)).ToString();
 
         public void CreateJsBundle(string bundleName, params string[] filePaths)
         {
@@ -82,7 +82,7 @@ namespace Umbraco.Web.Common.RuntimeMinification
             // affect this or vice versa.
         }
 
-        public string RenderJsHere(string bundleName) => _smidge.SmidgeHelper.JsHereAsync(bundleName, _hostingEnvironment.IsDebugMode).ToString();
+        public async Task<string> RenderJsHereAsync(string bundleName) => (await _smidge.SmidgeHelper.JsHereAsync(bundleName, _hostingEnvironment.IsDebugMode)).ToString();
 
         public async Task<IEnumerable<string>> GetAssetPathsAsync(string bundleName) => await _smidge.SmidgeHelper.GenerateJsUrlsAsync(bundleName, _hostingEnvironment.IsDebugMode);
 
diff --git a/src/Umbraco.Web.UI.NetCore/Areas/UmbracoBackOffice/Views/BackOffice/Default.cshtml b/src/Umbraco.Web.UI.NetCore/Areas/UmbracoBackOffice/Views/BackOffice/Default.cshtml
index cf205b3373..8378762cbc 100644
--- a/src/Umbraco.Web.UI.NetCore/Areas/UmbracoBackOffice/Views/BackOffice/Default.cshtml
+++ b/src/Umbraco.Web.UI.NetCore/Areas/UmbracoBackOffice/Views/BackOffice/Default.cshtml
@@ -1,17 +1,132 @@
-@{
-    Layout = null;
+@using Umbraco.Core
+@using Umbraco.Web.Composing
+@using Umbraco.Web
+@using Umbraco.Web.WebAssets
+@using Umbraco.Core.WebAssets
+@using Umbraco.Core.Configuration
+@using Umbraco.Core.Hosting
+@using Umbraco.Extensions
+@using Umbraco.Core.Logging
+@using Umbraco.Web.BackOffice.Controllers
+@using Microsoft.AspNetCore.Authentication
+@inject IAuthenticationSchemeProvider authenticationSchemeProvider
+@inject BackOfficeServerVariables backOfficeServerVariables
+@inject IUmbracoVersion umbracoVersion
+@inject IHostingEnvironment hostingEnvironment
+@inject IGlobalSettings globalSettings
+@inject IRuntimeMinifier runtimeMinifier
+@inject IProfilerHtml profilerHtml
+
+@{
+    var isDebug = false;
+    var qryDebug = Context.Request.Query["umbDebug"].TryConvertTo<bool>();
+    isDebug = qryDebug.Success && qryDebug.Result;
+    var backOfficePath = globalSettings.GetBackOfficePath(hostingEnvironment);
 }
-<!doctype html>
+
+<!DOCTYPE html>
+
 <html lang="en">
 <head>
-    
+    <base href="@backOfficePath.EnsureEndsWith('/')" />
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <meta name="apple-mobile-web-app-capable" content="yes">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
+    <meta name="robots" content="noindex, nofollow">
+    <meta name="pinterest" content="nopin" />
+
+    <title ng-bind="$root.locationTitle">Umbraco</title>
+
+    @Html.Raw(await runtimeMinifier.RenderCssHereAsync(BackOfficeWebAssets.UmbracoInitCssBundleName))
+
 </head>
+<body ng-class="{'touch':touchDevice, 'emptySection':emptySection, 'umb-drawer-is-visible':drawer.show, 'umb-tour-is-visible': tour.show, 'tabbing-active':tabbingActive}" ng-controller="Umbraco.MainController" id="umbracoMainPageBody">
 
-<body>
+    <noscript>
+        <div style="margin: 10px;">
+            <h3><img src="assets/img/application/logo.png" alt="Umbraco logo" style="vertical-align: text-bottom;" /> Umbraco</h3>
+            <p>For full functionality of Umbraco CMS it is necessary to enable JavaScript.</p>
+            <p>Here are the <a href="https://www.enable-javascript.com/" target="_blank" style="text-decoration: underline;">instructions how to enable JavaScript in your web browser</a>.</p>
+        </div>
+    </noscript>
 
-    <h1>Hello!</h1>
+    <div ng-hide="!authenticated" ng-cloak>
 
-    <p>TODO: Import the default.cshtml back office page</p>
+        <div style="display: none;" id="mainwrapper" class="clearfix">
+
+            <umb-app-header></umb-app-header>
+
+            <div class="umb-app-content">
+
+                <umb-navigation></umb-navigation>
+
+                <section id="contentwrapper">
+
+                    <div id="contentcolumn">
+                        <div class="umb-editor" ng-view></div>
+                    </div>
+
+                </section>
+
+            </div>
+
+            <umb-tour ng-if="tour.show"
+                      model="tour">
+            </umb-tour>
+
+            <umb-notifications></umb-notifications>
+
+        </div>
+
+        <!-- help dialog controller by the help button - this also forces the backoffice UI to shift 400px  -->
+        <umb-drawer data-element="drawer" ng-if="drawer.show" model="drawer.model" view="drawer.view"></umb-drawer>
+
+        <umb-search ng-if="search.show" on-close="closeSearch()"></umb-search>
+
+    </div>
+
+    <umb-backdrop ng-if="backdrop.show || infiniteMode"
+                  backdrop-opacity="backdrop.opacity"
+                  highlight-element="backdrop.element"
+                  highlight-prevent-click="backdrop.elementPreventClick"
+                  disable-events-on-click="backdrop.disableEventsOnClick">
+    </umb-backdrop>
+
+    <umb-overlay ng-if="overlay.show"
+                 model="overlay"
+                 position="{{overlay.position}}"
+                 view="overlay.view"
+                 parent-scope="overlay.parentScope">
+    </umb-overlay>
+
+    <umb-editors ng-show="infiniteMode"></umb-editors>
+
+    <umb-login ng-if="login.show"
+               on-login="hideLoginScreen()">
+    </umb-login>
+
+    @await Html.BareMinimumServerVariablesScriptAsync(backOfficeServerVariables)
+
+    <script>
+
+        document.angularReady = function(app) {
+            @await Html.AngularValueExternalLoginInfoScriptAsync(authenticationSchemeProvider, ViewData.GetExternalSignInError())
+            @Html.AngularValueResetPasswordCodeInfoScript(ViewData["PasswordResetCode"])
+            @await Html.AngularValueTinyMceAssetsAsync(runtimeMinifier)
+
+            //required for the noscript trick
+            document.getElementById("mainwrapper").style.display = "inherit";
+        }
+    </script>
     
+    <script src="lib/lazyload-js/lazyload.min.js"></script>
+    <script src="@Url.GetUrlWithCacheBust("Application", "BackOffice", null, hostingEnvironment, umbracoVersion, runtimeMinifier)"></script>
+
+    @if (isDebug)
+    {
+        @Html.Raw(profilerHtml.Render())
+    }
+
 </body>
 </html>
diff --git a/src/Umbraco.Web/Umbraco.Web.csproj b/src/Umbraco.Web/Umbraco.Web.csproj
index 2f70515426..20d6714778 100755
--- a/src/Umbraco.Web/Umbraco.Web.csproj
+++ b/src/Umbraco.Web/Umbraco.Web.csproj
@@ -261,7 +261,6 @@
     <Compile Include="Editors\MemberGroupController.cs" />
     <Compile Include="Composing\CompositionExtensions\Controllers.cs" />
     <Compile Include="HealthCheck\HealthCheckController.cs" />
-    <Compile Include="HtmlHelperBackOfficeExtensions.cs" />
     <Compile Include="Composing\ModuleInjector.cs" />
     <Compile Include="Mvc\FilteredControllerFactoryCollection.cs" />
     <Compile Include="Mvc\FilteredControllerFactoryCollectionBuilder.cs" />
diff --git a/src/Umbraco.Web/UrlHelperExtensions.cs b/src/Umbraco.Web/UrlHelperExtensions.cs
index fb775db5c3..3659168577 100644
--- a/src/Umbraco.Web/UrlHelperExtensions.cs
+++ b/src/Umbraco.Web/UrlHelperExtensions.cs
@@ -115,38 +115,8 @@ namespace Umbraco.Web
         }
 
 
-        /// <summary>
-        /// Return the Url for an action with a cache-busting hash appended
-        /// </summary>
-        /// <param name="url"></param>
-        /// <param name="actionName"></param>
-        /// <param name="controllerName"></param>
-        /// <param name="routeVals"></param>
-        /// <returns></returns>
-        public static string GetUrlWithCacheBust(this UrlHelper url, string actionName, string controllerName, RouteValueDictionary routeVals = null)
-        {
-            var applicationJs = url.Action(actionName, controllerName, routeVals);
-            applicationJs = applicationJs + "?umb__rnd=" + GetCacheBustHash();
-            return applicationJs;
-        }
+        
 
-        /// <summary>
-        ///
-        /// </summary>
-        /// <returns></returns>
-        public static string GetCacheBustHash()
-        {
-            //make a hash of umbraco and client dependency version
-            //in case the user bypasses the installer and just bumps the web.config or client dependency config
-
-            //if in debug mode, always burst the cache
-            if (Current.HostingEnvironment.IsDebugMode)
-            {
-                return DateTime.Now.Ticks.ToString(CultureInfo.InvariantCulture).GenerateHash();
-            }
-
-            var version = Current.UmbracoVersion.SemanticVersion.ToSemanticString();
-            return $"{version}.{Current.RuntimeMinifier.CacheBuster}".GenerateHash();
-        }
+        
     }
 }
diff --git a/src/Umbraco.Web/WebAssets/CDF/ClientDependencyRuntimeMinifier.cs b/src/Umbraco.Web/WebAssets/CDF/ClientDependencyRuntimeMinifier.cs
index cf0e001d3b..0cd03d2ee6 100644
--- a/src/Umbraco.Web/WebAssets/CDF/ClientDependencyRuntimeMinifier.cs
+++ b/src/Umbraco.Web/WebAssets/CDF/ClientDependencyRuntimeMinifier.cs
@@ -50,11 +50,11 @@ namespace Umbraco.Web.WebAssets.CDF
                 filePaths.Select(x => new CssFile(x)).ToArray());
         }
 
-        public string RenderCssHere(string bundleName)
+        public Task<string> RenderCssHereAsync(string bundleName)
         {
             var bundleFiles = GetCssBundleFiles(bundleName);
-            if (bundleFiles == null) return string.Empty;
-            return RenderOutput(bundleFiles, AssetType.Css);
+            if (bundleFiles == null) return Task.FromResult(string.Empty);
+            return Task.FromResult(RenderOutput(bundleFiles, AssetType.Css));
         }
 
         public void CreateJsBundle(string bundleName, params string[] filePaths)
@@ -67,11 +67,11 @@ namespace Umbraco.Web.WebAssets.CDF
                 filePaths.Select(x => new JavascriptFile(x)).ToArray());
         }
 
-        public string RenderJsHere(string bundleName)
+        public Task<string> RenderJsHereAsync(string bundleName)
         {
             var bundleFiles = GetJsBundleFiles(bundleName);
-            if (bundleFiles == null) return string.Empty;
-            return RenderOutput(bundleFiles, AssetType.Javascript);
+            if (bundleFiles == null) return Task.FromResult(string.Empty);
+            return Task.FromResult(RenderOutput(bundleFiles, AssetType.Javascript));
         }
 
         public Task<IEnumerable<string>> GetAssetPathsAsync(string bundleName)