[DNSB]

I've run into what appears to be a bug with Sigil 1.9.2 and fonts as reported by epubcheck.

I opened an epub to do a bit of editing, set the font encryption (request from the author) and closed it. When I re-opened it to do a few other changes, epubcheck was reporting that the fonts could not be decrypted. When I clicked on the font file to take a quick look at it, I did notice that instead of the font name, I was getting No reliable font data.

I then dumped the original font files into a sample epub and no issues. Added IDPF encryption and epubcheck complained. Generated another sample and tried Adobe encryption and epubcheck complained. With the two encrypted font epubs, I tried changing the encryption to none and the other encryption option and no errors were reported in the process but when I closed and reopened the epub, the encryption type hadn't changed.

A bit of further playing with a copy of Sigil 1.3.0 x86 that I still have installed did not show errors in epubcheck and I could change the encryption and after saving and re-opening the epub, the font encryption had appeared to change to none from IDPF. Still using Sigil 1.3.0, epubcheck showed no issues and clicking on the font file showed the expected. Going back to Sigil 1.9.2, clicking on the font file looked okay but epubcheck still complained the file could not be decrypted.

Edit: One item I should have mentioned is the fonts embedded in the epub were subsetted. For instance, in Aria BoldItalic, the 6 and 7 are missing.