AUCTeX font search dialog

[Robert Alessi]

Hello,

I don't know why, but it just so happens that this morning the font
search dialog of my emacs does not work anymore.  After opening a file
as simple as this one:

   \documentclass{article}

   \usepackage{fontspec}

   \begin{document}

   \end{document}

invoking C-C C-M then "setmainfont" brings me a font search dialog, as
expected, but this dialog is unable to search for anything.  Whatever
I type, I run into a No match error.

I didn't change anything in my settings, so I wonder if anyone has
noticed the same error in the last few days.

Best,

Robert