UnicodeEncodeError: 'utf-8' codec can't encode characters in position 6-7: surrogates not allowed

[Nelson A. de Oliveira]

While trying to convert a PDF to MOBI I am seeing this:

$ ebook-convert itil-etc.pdf itil-etc.mobi
1% Convertendo entrada para HTML...
InputFormatPlugin: PDF Input running
on /home/naoliv/curso/itil-etc.pdf
pdftohtml log:
Syntax Error: Expected the optional content group list, but wasn't able to find it, or it isn't an Array
Page-1
Page-2
Page-3
(...)
Page-171
Syntax Error: Expected the optional content group list, but wasn't able to find it, or it isn't an Array
Syntax Error: Expected the optional content group list, but wasn't able to find it, or it isn't an Array
Syntax Error: Expected the optional content group list, but wasn't able to find it, or it isn't an Array
Traceback (most recent call last):
  File "/usr/bin/ebook-convert", line 20, in <module>
    sys.exit(main())
  File "/usr/lib/calibre/calibre/ebooks/conversion/cli.py", line 401, in main
    plumber.run()
  File "/usr/lib/calibre/calibre/ebooks/conversion/plumber.py", line 1108, in run
    self.oeb = self.input_plugin(stream, self.opts,
  File "/usr/lib/calibre/calibre/customize/conversion.py", line 245, in __call__
    ret = self.convert(stream, options, file_ext,
  File "/usr/lib/calibre/calibre/ebooks/conversion/plugins/pdf_input.py", line 73, in convert
    opf.render(opffile)
  File "/usr/lib/calibre/calibre/ebooks/metadata/opf2.py", line 1521, in render
    item = E.item(id=unicode_type(ref.id), href=href)
  File "src/lxml/builder.py", line 210, in lxml.builder.ElementMaker.__call__
  File "src/lxml/builder.py", line 195, in lxml.builder.ElementMaker.__init__.add_dict
  File "src/lxml/etree.pyx", line 2429, in lxml.etree._Attrib.__setitem__
  File "src/lxml/apihelpers.pxi", line 593, in lxml.etree._setAttributeValue
  File "src/lxml/apihelpers.pxi", line 1532, in lxml.etree._utf8
UnicodeEncodeError: 'utf-8' codec can't encode characters in position 6-7: surrogates not allowed

Calibre is Debian's 4.99.4+dfsg+really4.17.0-1
"calibre --version" gives calibre 4.99.5
Python 2.7.18 and 3.8.3 are installed (I don't know if it's using 2 or 3)
locale has:

LANG=pt_BR.UTF-8
LANGUAGE=pt_BR:pt:en
LC_CTYPE="pt_BR.UTF-8"
LC_NUMERIC="pt_BR.UTF-8"
LC_TIME="pt_BR.UTF-8"
LC_COLLATE="pt_BR.UTF-8"
LC_MONETARY="pt_BR.UTF-8"
LC_MESSAGES="pt_BR.UTF-8"
LC_PAPER="pt_BR.UTF-8"
LC_NAME="pt_BR.UTF-8"
LC_ADDRESS="pt_BR.UTF-8"
LC_TELEPHONE="pt_BR.UTF-8"
LC_MEASUREMENT="pt_BR.UTF-8"
LC_IDENTIFICATION="pt_BR.UTF-8"
LC_ALL=

Do you need any more info, please?

[Kovid Goyal (kovid)]

I do not provide support for people using distro provided packages. If you are using a distro provided package, uninstall it and install the official calibre binary from https://calibre-ebook.com/download_linux and if you can reproduce the bug with that, re-open the ticket. Of course, if you are already using the official binary, apologies and feel free to re-open the ticket immediately :)

 status invalid

[Nelson A. de Oliveira (naoliv)]

I would test with the official installer, but it fails:

Extracting files to /opt/calibre ...
Extracting application files...
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "<string>", line 800, in script_launch
  File "<string>", line 756, in main
  File "<string>", line 707, in run_installer
  File "/usr/lib/python3.8/subprocess.py", line 340, in call
    with Popen(*popenargs, **kwargs) as p:
  File "/usr/lib/python3.8/subprocess.py", line 854, in __init__
    self._execute_child(args, executable, preexec_fn, close_fds,
  File "/usr/lib/python3.8/subprocess.py", line 1702, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: '/opt/calibre/calibre_postinstall'