Exception in folding when adding tags before a Background

[nemesv]

Steps to reproduce:

Given this feature file:

Feature: Test
   
    Background: 
        Given this is step

Type an @ character before the Background:

Feature: Test
   @
    Background: 
        Given this is step

com.jetbrains.rdclient.util.BackendException: left.IsValid() & right.IsValid()

--- EXCEPTION #1/2 [AssertionException]
Message = “left.IsValid() & right.IsValid()”
ExceptionPath = Root.InnerException
ClassName = JetBrains.Diagnostics.Assertion+AssertionException
HResult = COR_E_EXCEPTION=80131500
Source = JetBrains.Lifetimes
StackTraceString = “
at JetBrains.Diagnostics.Assertion.Fail(String message)
at JetBrains.DocumentModel.DocumentOffset.op_Subtraction(DocumentOffset left, DocumentOffset right)
at ReSharperPlugin.SpecflowRiderPlugin.Folding.SpecFlowFoldingProcessor.CalculateLength(Nullable`1 textRange, DocumentRange keywordRange, DocumentRange range) in C:\Work\Github\resharper-specflow\src\dotnet\ReSharperPlugin.SpecflowRiderPlugin\Folding\SpecFlowFoldingProcessor.cs:line 62