WebApp Azure Publish: I'm getting EF6 Model Validation Errors on my db-first WebApp (ASP.NET 4.8)

When publishing the latest version of my WebApp to the staging slot on Azure I've started getting the following errors immediately after the publish:

Server Error in '/' Application.
One or more validation errors were detected during model generation:

CodeFirstNamespace.AspNetUserLogins: : EntityType 'AspNetUserLogins' has no key defined. Define the key for this EntityType.
CodeFirstNamespace.AspNetUserTokens: : EntityType 'AspNetUserTokens' has no key defined. Define the key for this EntityType.
CodeFirstNamespace.companies: : EntityType 'companies' has no key defined. Define the key for this EntityType.

 ....etc etc..

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Data.Entity.ModelConfiguration.ModelValidationException: One or more validation errors were detected during model generation:

CodeFirstNamespace.AspNetUserLogins: : EntityType 'AspNetUserLogins' has no key defined. Define the key for this EntityType.
CodeFirstNamespace.AspNetUserTokens: : EntityType 'AspNetUserTokens' has no key defined. Define the key for this EntityType.
CodeFirstNamespace.companies: : EntityType 'companies' has no key defined. Define the key for this EntityType.

...etc etc...

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[ModelValidationException: One or more validation errors were detected during model generation:

CodeFirstNamespace.AspNetUserLogins: : EntityType 'AspNetUserLogins' has no key defined. Define the key for this EntityType.
CodeFirstNamespace.AspNetUserTokens: : EntityType 'AspNetUserTokens' has no key defined. Define the key for this EntityType.
CodeFirstNamespace.companies: : EntityType 'companies' has no key defined. Define the key for this EntityType.

   System.Data.Entity.Core.Metadata.Edm.EdmModel.Validate() +432
   System.Data.Entity.DbModelBuilder.Build(DbProviderManifest providerManifest, DbProviderInfo providerInfo) +319
   System.Data.Entity.DbModelBuilder.Build(DbConnection providerConnection) +55
   System.Data.Entity.Internal.LazyInternalContext.CreateModel(LazyInternalContext internalContext) +159
   System.Data.Entity.Internal.RetryLazy`2.GetValue(TInput input) +123
   System.Data.Entity.Internal.LazyInternalContext.InitializeContext() +646
   System.Data.Entity.Internal.InternalContext.Initialize() +21
   System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type entityType) +16
   System.Data.Entity.Internal.Linq.InternalSet`1.Initialize() +53
   System.Data.Entity.Internal.Linq.InternalSet`1.get_InternalContext() +16
   System.Data.Entity.Infrastructure.DbQuery`1.System.Linq.IQueryable.get_Provider() +38
   System.Linq.Queryable.Where(IQueryable`1 source, Expression`1 predicate) +83
   IMS2_App.Utility.CheckRole(ApplicationUser cu, String role) in C:\Users\kenni\source\repos\IMS-Azure\IMS2_App\Routines\Utility.vb:90
   IMS2_App.HomeController.SalesPipeline() in C:\Users\kenni\source\repos\IMS-Azure\IMS2_App\Controllers\HomeController.vb:250
   lambda_method(Closure , ControllerBase , Object[] ) +66
   System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) +19
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +169
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +27
   System.Web.Mvc.Async.<>c.<BeginInvokeSynchronousActionMethod>b__9_0(IAsyncResult asyncResult, ActionInvocation innerInvokeState) +24
   System.Web.Mvc.Async.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult) +31
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +33
   System.Web.Mvc.Async.<>c__DisplayClass11_0.<InvokeActionMethodFilterAsynchronouslyRecursive>b__0() +58
   System.Web.Mvc.Async.<>c__DisplayClass11_2.<InvokeActionMethodFilterAsynchronouslyRecursive>b__2() +228
   System.Web.Mvc.Async.<>c__DisplayClass7_0.<BeginInvokeActionMethodWithFilters>b__1(IAsyncResult asyncResult) +15
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +15
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +35
   System.Web.Mvc.Async.<>c__DisplayClass3_6.<BeginInvokeAction>b__4() +35
   System.Web.Mvc.Async.<>c__DisplayClass3_1.<BeginInvokeAction>b__1(IAsyncResult asyncResult) +100
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +15
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +29
   System.Web.Mvc.<>c.<BeginExecuteCore>b__152_1(IAsyncResult asyncResult, ExecuteCoreState innerState) +13
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +45
   System.Web.Mvc.<>c.<BeginExecute>b__151_2(IAsyncResult asyncResult, Controller controller) +15
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +22
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +27
   System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +12
   System.Web.Mvc.<>c.<BeginProcessRequest>b__20_1(IAsyncResult asyncResult, ProcessRequestState innerState) +28
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +29
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +11
   System.Web.Mvc.<>c__DisplayClass3_0.<EndProcessRequest>b__0() +24
   System.Web.Mvc.<>c__DisplayClass5_0.<Wrap>b__0() +15
   System.Web.Mvc.ServerExecuteHttpHandlerWrapper.Wrap(Func`1 func) +27
   System.Web.Mvc.ServerExecuteHttpHandlerWrapper.Wrap(Action action) +64
   System.Web.Mvc.ServerExecuteHttpHandlerAsyncWrapper.EndProcessRequest(IAsyncResult result) +71
   System.Web.HttpServerUtility.ExecuteInternal(IHttpHandler handler, TextWriter writer, Boolean preserveForm, Boolean setPreviousPage, VirtualPath path, VirtualPath filePath, String physPath, Exception error, String queryStringOverride) +1454

[HttpException (0x80004005): Error executing child request for handler 'System.Web.Mvc.HttpHandlerUtil+ServerExecuteHttpHandlerAsyncWrapper'.]
   System.Web.HttpServerUtility.ExecuteInternal(IHttpHandler handler, TextWriter writer, Boolean preserveForm, Boolean setPreviousPage, VirtualPath path, VirtualPath filePath, String physPath, Exception error, String queryStringOverride) +2363
   System.Web.HttpServerUtility.Execute(IHttpHandler handler, TextWriter writer, Boolean preserveForm, Boolean setPreviousPage) +78
   System.Web.HttpServerUtility.Execute(IHttpHandler handler, TextWriter writer, Boolean preserveForm) +26
   System.Web.HttpServerUtilityWrapper.Execute(IHttpHandler handler, TextWriter writer, Boolean preserveForm) +25
   System.Web.Mvc.Html.ChildActionExtensions.ActionHelper(HtmlHelper htmlHelper, String actionName, String controllerName, RouteValueDictionary routeValues, TextWriter textWriter) +466
   System.Web.Mvc.Html.ChildActionExtensions.Action(HtmlHelper htmlHelper, String actionName, String controllerName, RouteValueDictionary routeValues) +83
   System.Web.Mvc.Html.ChildActionExtensions.Action(HtmlHelper htmlHelper, String actionName) +14
   ASP._Page_Views_Home_Index_vbhtml.Execute() +677
   System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +197
   System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +105
   System.Web.WebPages.StartPage.RunPage() +19
   System.Web.WebPages.StartPage.ExecutePageHierarchy() +73
   System.Web.WebPages.StartPage.RunPage() +19
   System.Web.WebPages.StartPage.ExecutePageHierarchy() +73
   System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +78
   System.Web.Mvc.RazorView.RenderView(ViewContext viewContext, TextWriter writer, Object instance) +235
   System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext, TextWriter writer) +107
   System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) +291
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResult(ControllerContext controllerContext, ActionResult actionResult) +15
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +56
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +420
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList`1 filters, ActionResult actionResult) +52
   System.Web.Mvc.Async.<>c__DisplayClass3_6.<BeginInvokeAction>b__4() +197
   System.Web.Mvc.Async.<>c__DisplayClass3_1.<BeginInvokeAction>b__1(IAsyncResult asyncResult) +100
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +15
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +29
   System.Web.Mvc.<>c.<BeginExecuteCore>b__152_1(IAsyncResult asyncResult, ExecuteCoreState innerState) +13
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +45
   System.Web.Mvc.<>c.<BeginExecute>b__151_2(IAsyncResult asyncResult, Controller controller) +15
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +22
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +27
   System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +12
   System.Web.Mvc.<>c.<BeginProcessRequest>b__20_1(IAsyncResult asyncResult, ProcessRequestState innerState) +28
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +50
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +29
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +11
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +576
   System.Web.<>c__DisplayClass285_0.<ExecuteStepImpl>b__0() +26
   System.Web.StepInvoker.Invoke(Action executionStep) +100
   System.Web.<>c__DisplayClass4_0.<Invoke>b__0() +22
   Microsoft.AspNet.TelemetryCorrelation.TelemetryCorrelationHttpModule.OnExecuteRequestStep(HttpContextBase context, Action step) +65
   System.Web.<>c__DisplayClass284_0.<OnExecuteRequestStep>b__0(Action nextStepAction) +54
   System.Web.StepInvoker.Invoke(Action executionStep) +84
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +100
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +163

The application works just fine on the development system and also on the live system (using the same db as the staging slot) which continues to work faultlessly.

The exception appears to be thrown by the linq handler when querying the context - presumably a lazy validation is then happening and all these exceptions are being thrown. However they seemingly aren't valid and the code works fine on the devbox.

The publish profile substitutes the Azure connection string in the various .config files.

I wasn't aware I'd made anything other than minor changes to the system and seeing as the app is resolutely db-first it was alarming to see 'CodeFirstNamespace.'s appearing in the exception and the DBModelBuilder firing up.

Is Azure trying to run a migration/initializer when it shouldn't?

Solved. The rather unsatisfying solution I found was to delete the deployment slot and create a new publish profile based thereon.

I can only guess that I'd somehow managed to bork the deployment slot - though looking at the pubxml files I do see some differences/extra fields (though nothing that jumps out as causing EF a headache).