anchor.diff:                  sb.Clear()
               else new StringBuilder(MinimumCapacity)
   
  -    static member Return (sb: StringBuilder) =
  +    static member internal Release (sb : StringBuilder) =
           if sb.Capacity <= MaximumCapacity then
               StringBuilderPool.instance <- sb
               StringBuilderPool.created  <- DateTimeOffset.Now
  
positive.code:     let chars = ArrayPool<char>.Shared.Rent sb.Length
      sb.CopyTo(0, chars, 0, sb.Length)
      let result = Encoding.UTF8.GetBytes(chars, 0, sb.Length)
      StringBuilderPool.Return sb
      ArrayPool<char>.Shared.Return chars
      result
  
  
negative.code:     [<DefaultValue; ThreadStatic>]
      static val mutable private created : DateTimeOffset
  
      static member public IsEnabled
          with get ()   = StringBuilderPool.isEnabled
          and  set flag = StringBuilderPool.isEnabled <- flag
  
      static member internal Rent () =
          match StringBuilderPool.IsEnabled with
          | false -> new StringBuilder(MinimumCapacity)
          | true  ->
              let lifetime = DateTimeOffset.Now - StringBuilderPool.created
              let expired  = lifetime > MaximumLifetime
              let sb       = StringBuilderPool.instance
  