Hi Itaļ, Luke, Braun,

Sorry for late response. It seems that I managed to fix the bug of
preview-latex you reported before. I don't speak Postscript and the fix
is totally heuristic, but it simply works, at least for me.

The attached patch removes a newline in the middle of initial string
sent to ghostscript. This newline was interpreted as a delimeter as
ghostscript, thus ghostscript responded twice to the initial string, if
my speculation is right, which led to a spurious prompt from
ghostscript.

Could you please test whether this patch fixes the problem on your side
if possible?

Best regards,
Ikumi Keita