Error in Forms when viewing preview #3493

Experiencing the following error when using Forms Commercial Module:-

InvalidOperationException: The layout view '~/Themes/Lepton/Layouts/Empty/Default.cshtml' could not be located. The following locations were searched:
~/Themes/Lepton/Layouts/Empty/Default.cshtml

If you're creating a bug/problem report, please include followings:

• ABP Framework version: v6.0.0-rc.1

• UI type: MVC

• DB provider: EF Core

• Tiered (MVC) or Identity Server Separated (Angular): Microservice

• Exception message and stack trace:
  System.InvalidOperationException: The layout view '~/Themes/Lepton/Layouts/Empty/Default.cshtml' could not be located. The following locations were searched:
  ~/Themes/Lepton/Layouts/Empty/Default.cshtml
  at Microsoft.AspNetCore.Mvc.Razor.RazorView.GetLayoutPage(ViewContext context, String executingFilePath, String layoutPath)
  at Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderLayoutAsync(ViewContext context, ViewBufferTextWriter bodyWriter)
  at Microsoft.AspNetCore.Mvc.Razor.RazorView.RenderAsync(ViewContext context)
  at Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor.ExecuteAsync(ViewContext viewContext, String contentType, Nullable1 statusCode) at Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor.ExecuteAsync(ViewContext viewContext, String contentType, Nullable1 statusCode)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeResultAsync>g__Logged|22_0(ResourceInvoker invoker, IActionResult result)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResultFilterAsync>g__Awaited|30_0[TFilter,TFilterAsync](ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResultExecutedContextSealed context)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.ResultNext[TFilter,TFilterAsync](State& next, Scope& scope, Object& state, Boolean& isCompleted)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeResultFilters>g__Awaited|28_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResourceFilter>g__Awaited|25_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|20_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Logged|17_1(ResourceInvoker invoker)
  at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Logged|17_1(ResourceInvoker invoker)
  at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
  at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
  at Volo.Abp.AspNetCore.Serilog.AbpSerilogMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
  at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
  --- End of stack trace from previous location ---
  at Volo.Abp.AspNetCore.MultiTenancy.MultiTenancyMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
  at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
  --- End of stack trace from previous location ---
  at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
  at Prometheus.HttpMetrics.HttpRequestDurationMiddleware.Invoke(HttpContext context)
  at Prometheus.HttpMetrics.HttpRequestCountMiddleware.Invoke(HttpContext context)
  at Prometheus.HttpMetrics.HttpInProgressMiddleware.Invoke(HttpContext context)
  at Volo.Abp.AspNetCore.Security.AbpSecurityHeadersMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
  at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
  --- End of stack trace from previous location ---
  at Volo.Abp.AspNetCore.Tracing.AbpCorrelationIdMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
  at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
  --- End of stack trace from previous location ---
  at Microsoft.AspNetCore.Localization.RequestLocalizationMiddleware.Invoke(HttpContext context)
  at Microsoft.AspNetCore.RequestLocalization.AbpRequestLocalizationMiddleware.InvokeAsync(HttpContext context, RequestDelegate next)
  at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass6_1.<<UseMiddlewareInterface>b__1>d.MoveNext()
  --- End of stack trace from previous location ---
  at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

• Steps to reproduce the issue:"