The 'calibre' programme (which I use for conversion for PDF to EPUB) fail to convert some PDF.According to 'calibre's devloper the bug is in windows version of pdftohtml.However he states that Linux and os x doesn't have any issues.
-- GitLab Migration Automatic Message -- This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity. You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/poppler/poppler/issues/391.
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.