https://dev.azure.com/umbraco/D-Team%20Tracker/_workitems/edit/10710

No not use IBackOfficeSecurity in UmbracoContext. Not we use IHttpContextAccessor to get the info about whether the current user is null or not. It is expected to be null in background jobs.

src/Umbraco.Tests.UnitTests/TestHelpers/Objects/TestUmbracoContextFactory.cs

@@ -8,7 +8,6 @@ using Umbraco.Cms.Core.Configuration.Models;
 using Umbraco.Cms.Core.Hosting;
 using Umbraco.Cms.Core.PublishedCache;
 using Umbraco.Cms.Core.Routing;
-using Umbraco.Cms.Core.Security;
 using Umbraco.Cms.Core.Web;
 using Umbraco.Cms.Tests.Common;
 using Umbraco.Cms.Web.Common.AspNetCore;
@@ -57,9 +56,6 @@ namespace Umbraco.Cms.Tests.UnitTests.TestHelpers.Objects
 
             IHostingEnvironment hostingEnvironment = TestHelper.GetHostingEnvironment();
 
-            var backofficeSecurityAccessorMock = new Mock<IBackOfficeSecurityAccessor>();
-            backofficeSecurityAccessorMock.Setup(x => x.BackOfficeSecurity).Returns(Mock.Of<IBackOfficeSecurity>());
-
             var umbracoContextFactory = new UmbracoContextFactory(
                 umbracoContextAccessor,
                 snapshotService.Object,
@@ -70,7 +66,7 @@ namespace Umbraco.Cms.Tests.UnitTests.TestHelpers.Objects
                 new UriUtility(hostingEnvironment),
                 new AspNetCoreCookieManager(httpContextAccessor),
                 Mock.Of<IRequestAccessor>(),
-                backofficeSecurityAccessorMock.Object);
+                httpContextAccessor);
 
             return umbracoContextFactory;
         }

src/Umbraco.Web.Common/UmbracoContext/UmbracoContext.cs

@@ -1,10 +1,10 @@
 using System;
+using Microsoft.AspNetCore.Http;
 using Umbraco.Cms.Core;
 using Umbraco.Cms.Core.Hosting;
 using Umbraco.Cms.Core.Models.PublishedContent;
 using Umbraco.Cms.Core.PublishedCache;
 using Umbraco.Cms.Core.Routing;
-using Umbraco.Cms.Core.Security;
 using Umbraco.Cms.Core.Web;
 using Umbraco.Extensions;
 
@@ -19,10 +19,10 @@ namespace Umbraco.Cms.Web.Common.UmbracoContext
         private readonly UriUtility _uriUtility;
         private readonly ICookieManager _cookieManager;
         private readonly IRequestAccessor _requestAccessor;
+        private readonly IHttpContextAccessor _httpContextAccessor;
         private readonly Lazy<IPublishedSnapshot> _publishedSnapshot;
         private string _previewToken;
         private bool? _previewing;
-        private readonly IBackOfficeSecurity _backofficeSecurity;
         private readonly UmbracoRequestPaths _umbracoRequestPaths;
         private Uri _originalRequestUrl;
         private Uri _cleanedUmbracoUrl;
@@ -33,13 +33,13 @@ namespace Umbraco.Cms.Web.Common.UmbracoContext
         // warn: does *not* manage setting any IUmbracoContextAccessor
         internal UmbracoContext(
             IPublishedSnapshotService publishedSnapshotService,
-            IBackOfficeSecurity backofficeSecurity,
             UmbracoRequestPaths umbracoRequestPaths,
             IHostingEnvironment hostingEnvironment,
             IVariationContextAccessor variationContextAccessor,
             UriUtility uriUtility,
             ICookieManager cookieManager,
-            IRequestAccessor requestAccessor)
+            IRequestAccessor requestAccessor,
+            IHttpContextAccessor httpContextAccessor)
         {
             if (publishedSnapshotService == null)
             {
@@ -51,10 +51,9 @@ namespace Umbraco.Cms.Web.Common.UmbracoContext
             _hostingEnvironment = hostingEnvironment;
             _cookieManager = cookieManager;
             _requestAccessor = requestAccessor;
-
+            _httpContextAccessor = httpContextAccessor;
             ObjectCreated = DateTime.Now;
             UmbracoRequestId = Guid.NewGuid();
-            _backofficeSecurity = backofficeSecurity ?? throw new ArgumentNullException(nameof(backofficeSecurity));
             _umbracoRequestPaths = umbracoRequestPaths;
 
             // beware - we cannot expect a current user here, so detecting preview mode must be a lazy thing
@@ -143,7 +142,7 @@ namespace Umbraco.Cms.Web.Common.UmbracoContext
             Uri requestUrl = _requestAccessor.GetRequestUrl();
             if (requestUrl != null
                 && _umbracoRequestPaths.IsBackOfficeRequest(requestUrl.AbsolutePath) == false
-                && _backofficeSecurity.CurrentUser != null)
+                && _httpContextAccessor.HttpContext?.GetCurrentIdentity() != null)
             {
                 var previewToken = _cookieManager.GetCookieValue(Core.Constants.Web.PreviewCookieName); // may be null or empty
                 _previewToken = previewToken.IsNullOrWhiteSpace() ? null : previewToken;

src/Umbraco.Web.Common/UmbracoContext/UmbracoContextFactory.cs

@@ -1,10 +1,10 @@
 using System;
+using Microsoft.AspNetCore.Http;
 using Umbraco.Cms.Core;
 using Umbraco.Cms.Core.Hosting;
 using Umbraco.Cms.Core.Models.PublishedContent;
 using Umbraco.Cms.Core.PublishedCache;
 using Umbraco.Cms.Core.Routing;
-using Umbraco.Cms.Core.Security;
 using Umbraco.Cms.Core.Web;
 
 namespace Umbraco.Cms.Web.Common.UmbracoContext
@@ -23,7 +23,7 @@ namespace Umbraco.Cms.Web.Common.UmbracoContext
         private readonly IHostingEnvironment _hostingEnvironment;
         private readonly ICookieManager _cookieManager;
         private readonly IRequestAccessor _requestAccessor;
-        private readonly IBackOfficeSecurityAccessor _backofficeSecurityAccessor;
+        private readonly IHttpContextAccessor _httpContextAccessor;
         private readonly UriUtility _uriUtility;
 
         /// <summary>
@@ -39,7 +39,7 @@ namespace Umbraco.Cms.Web.Common.UmbracoContext
             UriUtility uriUtility,
             ICookieManager cookieManager,
             IRequestAccessor requestAccessor,
-            IBackOfficeSecurityAccessor backofficeSecurityAccessor)
+            IHttpContextAccessor httpContextAccessor)
         {
             _umbracoContextAccessor = umbracoContextAccessor ?? throw new ArgumentNullException(nameof(umbracoContextAccessor));
             _publishedSnapshotService = publishedSnapshotService ?? throw new ArgumentNullException(nameof(publishedSnapshotService));
@@ -50,7 +50,7 @@ namespace Umbraco.Cms.Web.Common.UmbracoContext
             _uriUtility = uriUtility ?? throw new ArgumentNullException(nameof(uriUtility));
             _cookieManager = cookieManager ?? throw new ArgumentNullException(nameof(cookieManager));
             _requestAccessor = requestAccessor ?? throw new ArgumentNullException(nameof(requestAccessor));
-            _backofficeSecurityAccessor = backofficeSecurityAccessor ?? throw new ArgumentNullException(nameof(backofficeSecurityAccessor));
+            _httpContextAccessor = httpContextAccessor ?? throw new ArgumentNullException(nameof(httpContextAccessor));
         }
 
         private IUmbracoContext CreateUmbracoContext()
@@ -75,13 +75,13 @@ namespace Umbraco.Cms.Web.Common.UmbracoContext
 
             return new UmbracoContext(
                 _publishedSnapshotService,
-                _backofficeSecurityAccessor.BackOfficeSecurity,
                 _umbracoRequestPaths,
                 _hostingEnvironment,
                 _variationContextAccessor,
                 _uriUtility,
                 _cookieManager,
-                _requestAccessor);
+                _requestAccessor,
+                _httpContextAccessor);
         }
 
         /// <inheritdoc />