Re: gtk mule-fonts note
The reason for using this tag is to tell Custom _not_ to clear those
fonts from the faces. I don't know what Custom currently does
Its code does not even contain `mule-fonts' symbol. XEmacs core only
defines this tag on certain occasions, as described in
<02553f85227c66-gin(a)mo.msk.ru>, and does not use it otherwise. It is
used, however, by x-symbol package.