Error when converting to mobi

[seannymurrs]

Describe the bug/problem
When trying to convert an epub to mobi (to email), the task fails.

To Reproduce
Steps to reproduce the behavior:

1. Go to a book.
2. Click on the option to convert to mobi and email.
3. Scroll down to the task list.
4. See error

Logfile

cps.tasks.convert:207} 
[2021-04-01 22:14:57,105] DEBUG {cps.tasks.convert:222} Failed to import PyQt module: PyQt5.QtGui with error: libGL.so.1: cannot open shared object file: No such file or directory
[2021-04-01 22:14:57,105] DEBUG {cps.tasks.convert:222} Traceback (most recent call last):
[2021-04-01 22:14:57,105] DEBUG {cps.tasks.convert:222}   File "runpy.py", line 194, in _run_module_as_main
[2021-04-01 22:14:57,105] DEBUG {cps.tasks.convert:222}   File "runpy.py", line 87, in _run_code
[2021-04-01 22:14:57,106] DEBUG {cps.tasks.convert:222}   File "site.py", line 45, in <module>
[2021-04-01 22:14:57,106] DEBUG {cps.tasks.convert:222}   File "site.py", line 41, in main
[2021-04-01 22:14:57,106] DEBUG {cps.tasks.convert:222}   File "calibre/ebooks/conversion/cli.py", line 401, in main
[2021-04-01 22:14:57,106] DEBUG {cps.tasks.convert:222}   File "calibre/ebooks/conversion/plumber.py", line 1271, in run
[2021-04-01 22:14:57,106] DEBUG {cps.tasks.convert:222}   File "calibre/ebooks/conversion/plugins/mobi_output.py", line 186, in convert
[2021-04-01 22:14:57,106] DEBUG {cps.tasks.convert:222}   File "bypy-importer.py", line 203, in exec_module
[2021-04-01 22:14:57,106] DEBUG {cps.tasks.convert:222}   File "calibre/ebooks/mobi/writer2/resources.py", line 12, in <module>
[2021-04-01 22:14:57,107] DEBUG {cps.tasks.convert:222}   File "bypy-importer.py", line 203, in exec_module
[2021-04-01 22:14:57,107] DEBUG {cps.tasks.convert:222}   File "calibre/ebooks/mobi/utils.py", line 13, in <module>
[2021-04-01 22:14:57,107] DEBUG {cps.tasks.convert:222}   File "bypy-importer.py", line 203, in exec_module
[2021-04-01 22:14:57,107] DEBUG {cps.tasks.convert:222}   File "calibre/utils/img.py", line 13, in <module>
[2021-04-01 22:14:57,107] DEBUG {cps.tasks.convert:222} ImportError: cannot import name 'QColor' from 'qt.core' (/mnt/mpaths/seannymurrs/calibre-bin/calibre/lib/calibre-extensions/python-lib.bypy.frozen/qt/core.pyc)
[2021-04-01 22:14:57,108]  INFO {cps.tasks.convert:140} ebook converter failed with error while converting book

Expected behavior
I expected the epub to be converted and emailed.

[cbartondock]

If you're on linux
sudo apt update sudo apt install libgl1-mesa-glx

See conda-forge/pygridgen-feedstock#10

[OzzieIsaacs]

This is a problem with calibre and not with calibre-web. I never had problems with missing libraries from calibre. Please report this issue at the docker container repo (if applicable) or calibre itself. For helping them fixing the problem please make sure to include all information regarding your setup.