[plt-scheme] Syntax-objects in DrScheme

Hi all,

I have noticed something I'd like to improve,
but first I need to figure out the cause:

Try this expression in the DrScheme repl:

   (with-syntax ([(x ...) #'(x1 x2 x3)])
     (syntax
       (y x ... z)))

The results is a syntax-object #'(y x1 x2 x3 z).
Click on the blue arrow to see the contents.

  - click on y
    => y becomes green and you can inspect
       the syntax properties of y

  - click on x1
    => x1 becomes green and you can inspect
       the syntax properties of x1

  - click on x2
    => The entire expression becomes green
       and you can not inspect the syntax-properties
       of x2

  - click on x3
    => The entire expression becomes green
       and you can not inspect the syntax-properties
       of x3

  - click on z
    => The entire expression becomes green
       and you can not inspect the syntax-properties
       of z

It is the ... in (syntax (y x ... z)) that
provokes the behaviour, but why?

-- 
Jens Axel Søgaard