Gtk: BadMatch when running any app in a browser on Linux with the ES2 pipeline

I get the following BadMatch error while running any app in a browser on Linux with the ES2 pipeline

JRE 1.7.0.06.ea: The program '<unknown>' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadMatch (invalid parameter attributes)'.
  (Details: serial 67 error_code 8 request_code 128 minor_code 5)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the --sync command line
   option to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)

I suspect that this is caused by Glass not using the requested visual id to create the child window, but I haven't yet proven this. I have attached the output of running Firefox with JPI_PLUGIN2_DEBUG=true and JPI_PLUGIN2_VERBOSE=true in case this is useful.