Hi All,
This bug is now fixed in Sigil master. It will hit any OPF file that does not start with an xml declaration line:
Code:
<?xml version="1.0" encoding="utf-8" ?>
So the workaround is to edit the opf file and add an xml declaration to the first line of the file. Sigil does this automatically which is why we have not seen this bug reported before.
This bug fix will appear in the next release.
KevinH