[pirl8]

I'm trying to convert an ePub containing embedded fonts to AZW3 format, but my Kindle Touch does not find them, while it does if I convert the file via KindleGen.

What i'm doing is:

1. edit ePub with sigil;
2. add needed fonts to the "Fonts" subdir. This results in a new line in content.opf file:
   

   "<item href="Fonts/gi.ttf" id="my.ttf" media-type="application/x-font-ttf" />

3. add @font-face definitions to CSS:
   

   @font-face {
     font-family: "MyFont";
     font-weight: normal;
     font-style: normal;
     src: url(../Fonts/my.ttf);
   }

4. add Font-Family: MyFont where needed.

Then I save the file and convert it to AZW3 with calibre, but my Kindle (firmware 5.1.0) does not show an option to enable them.

If I process the same file with KindleGen, everything is working fine.

What am I doing wrong?