Error cailbre 8.11.1 calibre-debug --gui Mint 22.2

gbm · 09-27-2025, 12:53 AM

Code:

$ calibre-debug --gui
calibre 8.11.1  embedded-python: True
Linux-6.14.0-32-generic-x86_64-with-glibc2.39 Linux ('64bit', 'ELF')
('Linux', '6.14.0-32-generic', '#32~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Tue Sep  2 14:21:04 UTC 2')
Python 3.11.13
Interface language: None
EXE path: /opt/calibre/bin/calibre-debug
Successfully initialized third party plugins: ACSM Input (0, 1, 0) && Gather KFX-ZIP (from KFX Input) (2, 26, 2) && DeDRM (10, 0, 9) && Package KFX (from KFX Input) (2, 26, 2) && ACSM Input Plugin GUI Extension (0, 1, 0) && Baen (1, 1, 0) && Barnes & Noble (1, 5, 7) && Diaps Editing Toolbag (0, 5, 0) && EpubMerge (3, 2, 0) && EpubSplit (3, 12, 0) && Goodreads (1, 8, 3) && Hyphenate This! (0, 1, 3) && KFX metadata reader (from KFX Input) (2, 26, 2) && From KFX (2, 26, 2) && KFX Input (2, 26, 2) && KindleUnpack - The Plugin (0, 83, 8) && Kobo Utilities (2, 24, 3) && Modify ePub (1, 8, 6) && Quality Check (1, 14, 2)
QPA platform: xcb
devicePixelRatio: 1.09375
logicalDpi: 96.0 x 96.0
physicalDpi: 84.58633776091081 x 84.69527027027027
ApplicationPaletteChange event ignored
Using calibre Qt style: True
Traceback (most recent call last):
  File "runpy.py", line 198, in _run_module_as_main
  File "runpy.py", line 88, in _run_code
  File "site.py", line 47, in <module>
  File "site.py", line 43, in main
  File "calibre/debug.py", line 234, in main
  File "calibre/gui_launch.py", line 74, in calibre
  File "calibre/gui2/main.py", line 548, in main
  File "calibre/gui2/main.py", line 560, in run_main
  File "calibre/gui2/main.py", line 398, in run_gui
  File "calibre/gui2/main.py", line 408, in run_gui_
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/ui.py", line 51, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/init.py", line 37, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/library/alternate_views.py", line 67, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/pin_columns.py", line 9, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/library/delegates.py", line 46, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/dialogs/comments_dialog.py", line 11, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/comments_editor.py", line 14, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "html5_parser/__init__.py", line 31, in <module>
RuntimeError: html5-parser and lxml are using different versions of libxml2. This happens commonly when using pip installed versions of lxml. Use pip install --no-binary lxml lxml instead. libxml2 versions: html5-parser: (2, 9, 14) != lxml: (2, 15, 0)

Only happens when try to run in debug.

bernie

kovidgoyal · 09-27-2025, 01:12 AM

Doesn't reproduce for me. Are the env vars the same when you run calibre and calibre-debug --gui?

gbm · 09-27-2025, 03:24 PM

This is a fresh install of Linux Mint 22.2 on a new disk. Calibre also does not start when using "Restart in debug mode".

Did a calibre-uninstall then a clean install of 8.11.1 same result.

Reverted to 8.10 calibre-debug works.

Code:

$ calibre-debug --gui
calibre 8.10  embedded-python: True
Linux-6.14.0-32-generic-x86_64-with-glibc2.39 Linux ('64bit', 'ELF')
('Linux', '6.14.0-32-generic', '#32~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Tue Sep  2 14:21:04 UTC 2')
Python 3.11.12
Interface language: None
EXE path: /opt/calibre/bin/calibre-debug
Successfully initialized third party plugins: ACSM Input (0, 1, 0) && Gather KFX-ZIP (from KFX Input) (2, 26, 2) && DeDRM (10, 0, 9) && Package KFX (from KFX Input) (2, 26, 2) && ACSM Input Plugin GUI Extension (0, 1, 0) && Baen (1, 1, 0) && Barnes & Noble (1, 5, 7) && Diaps Editing Toolbag (0, 5, 0) && EpubMerge (3, 2, 0) && EpubSplit (3, 12, 0) && Goodreads (1, 8, 3) && Hyphenate This! (0, 1, 3) && KFX metadata reader (from KFX Input) (2, 26, 2) && From KFX (2, 26, 2) && KFX Input (2, 26, 2) && KindleUnpack - The Plugin (0, 83, 8) && Kobo Utilities (2, 24, 3) && Modify ePub (1, 8, 6) && Quality Check (1, 14, 2)
QPA platform: xcb
devicePixelRatio: 1.09375
logicalDpi: 96.0 x 96.0
physicalDpi: 84.58633776091081 x 84.69527027027027
ApplicationPaletteChange event ignored
Using calibre Qt style: True
[0.00] Starting up...
Spoiler: 

[0.00] Showing splash screen...
[1.08] splash screen shown
[1.08] Initializing db...
[1.21] db initialized
[1.21] Constructing main UI...
[1.89] [DEBUG] [koboutilities.config:<module>:75] CreateNewCustomColumn is supported
ACSM Input: GUI Plugin Genesis!
qt.gui.imageio: libpng warning: iCCP: known incorrect sRGB profile
[2.10] [DEBUG] [koboutilities.action:KoboUtilitiesAction.genesis:121] Running in optimized mode
qt.gui.imageio: libpng warning: iCCP: known incorrect sRGB profile
[2.63] GUI main window shown
EpubMerge: DEBUG: 2025-09-27 14:20:43,433: calibre_plugins.epubmerge.epubmerge_plugin(156): macmenuhack file_path:/home/gbmoore/.config/calibre/plugins/fanficfare_macmenuhack.txt
[2.67] [DEBUG] [koboutilities.config:get_library_config:638] library_config: {'SchemaVersion': 1,
 'profiles': {'Default': {'customColumnOptions': {'currentReadingLocationColumn': '#folder',
                                                  'lastReadColumn': '',
                                                  'percentReadColumn': '',
                                                  'ratingColumn': 'rating',
                                                  'restOfBookEstimateColumn': '',
                                                  'timeSpentReadingColumn': ''},
                          'forDevice': None,
                          'profileName': 'Default',
                          'storeOptionsStore': {'doNotStoreIfReopened': False,
                                                'promptToStore': True,
                                                'storeIfMoreRecent': False,
                                                'storeOnConnect': False},
                          'updateOptionsStore': {'doEarlyFirmwareUpdate': False,
                                                 'doFirmwareUpdateCheck': False,
                                                 'firmwareUpdateCheckLastTime': 0}}},
 'readingPositionChangesStore': {'selectBooksInLibrary': False,
                                 'updeateGoodreadsProgress': False},
 'shelvesColumn': None}
[2.67] [DEBUG] [koboutilities.action:KoboUtilitiesAction.device_driver_name:759] could not load extended driver. Exception= No module named 'calibre_plugins.kobotouch_extended'
[2.67] [DEBUG] [koboutilities.action:KoboUtilitiesAction.set_toolbar_button_tooltip:181] setting to text='Utilities to use with Kobo ereaders

Driver: KoboTouch'
[2.76] main UI initialized...
[2.76] Hiding splash screen
[2.76] splash screen hidden
[2.76] Started up in 2.76 seconds with 1318 books

Quote:

Originally Posted by kovidgoyal

Doesn't reproduce for me. Are the env vars the same when you run calibre and calibre-debug --gui?

kovidgoyal · 09-27-2025, 11:15 PM

Strange, dont see how that's possible. Try

LD_DEBUG=libs ./calibre-debug -g 2>&1 | grep libxml2

and post the output.

gbm · 09-28-2025, 12:06 AM

Got a head of myself.

Code:

RuntimeError: html5-parser and lxml are using different versions of libxml2. This happens commonly when using pip installed versions of lxml. Use pip install --no-binary lxml lxml instead. libxml2 versions: html5-parser: (2, 9, 14) != lxml: (2, 15, 0)

bernie

Quote:

Originally Posted by kovidgoyal

Strange, dont see how that's possible. Try

LD_DEBUG=libs ./calibre-debug -g 2>&1 | grep libxml2

and post the output.

kovidgoyal · 09-28-2025, 01:11 AM

Yeah I want the output from LD_DEBUG, that message doesnt tell me where the older libxml2 is coming from

gbm · 09-28-2025, 01:49 AM

It did not print any out put but I do have:

Code:

libxml2.so.2.9.14 /lib/x86_64-linux-gnu

Code:

libxml2.so.2.13.8 /var/lib/flatpak/runtime/org.freedesktop.Platform/x86_64/24.08/e2cda5d7700bf0f02c764e151918a6e93def2634e8df9dc0dec52c4a1923ef88/files/lib/x86_64-linux-gnu

Code:

libxml2.so.2.13.8 /var/lib/flatpak/runtime/org.kde.Platform/x86_64/5.15-24.08/79fbdb22e166f20c4ca1f6639415d8dac00cfe64b07ab18d0f5a875c73942225/files/lib/x86_64-linux-gnu

bernie

Going to bed.
8.11.1 works except for debug gui.

Quote:

Originally Posted by kovidgoyal

Yeah I want the output from LD_DEBUG, that message doesnt tell me where the older libxml2 is coming from

kovidgoyal · 09-28-2025, 02:47 AM

And what does

ldd ./lib/calibre-extensions/html5_parser.html_parser.so

output?

kovidgoyal · 09-28-2025, 05:53 AM

I tried this in a debian:stable container which has libxml2.so.2.19.4 and couldnt reproduce there either.

gbm · 09-28-2025, 06:47 PM

8.10.0

Code:

LD_DEBUG=libs ./calibre-debug -g 2>&1 | grep libxml2 grep libxml2 
grep: grep: No such file or directory
grep: libxml2: No such file or directory

Code:

ldd: ./lib/calibre-extensions/html5_parser.html_parser.so: No such file or directory

8.11.1

Code:

LD_DEBUG=libs ./calibre-debug -g 2>&1 | grep libxml2 grep libxml2 
grep: grep: No such file or directory
grep: libxml2: No such file or directory

Code:

ldd: ./lib/calibre-extensions/html5_parser.html_parser.so: No such file or directory

I get the same result with my old system disk. 8.10.0 calibre debug works 8.11.1 calibre debug does not work.

bernie

Quote:

Originally Posted by kovidgoyal

And what does

ldd ./lib/calibre-extensions/html5_parser.html_parser.so

output?

gbm · 09-28-2025, 07:36 PM

Ok installed calibre 8 on a Mint 22.2 live usb and calibre debug worked.

Will install on different disk or vm and test without and with the flatpacks I use. Will be tomorrow or Tuesday.

bernie

kovidgoyal · 09-29-2025, 12:14 AM

You need just grep libxml2 not grep libxml2 grep libxml

And run the ldd comman inside the calibre installation dir, typically /opt/calibre

gbm · 10-03-2025, 02:53 AM

Sorry to get back so late, my monitor died.

Updated to calibre 8.12 still the same error. calibre launches using the calibre command or launcher.

Code:

/opt/calibre$ ldd ./lib/calibre-extensions/html5_parser.html_parser.so 
	linux-vdso.so.1 (0x00007fe1a9c34000)
	libxml2.so.16 => not found
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fe1a9800000)
	/lib64/ld-linux-x86-64.so.2 (0x00007fe1a9c36000)

Code:

/opt/calibre$ LD_DEBUG=libs ./calibre-debug -g 2>&1 | grep libxml2
     22233:	find library=libxml2.so.16 [0]; searching
     22233:	  trying file=/opt/calibre/lib/libxml2.so.16
     22233:	calling init: /opt/calibre/lib/libxml2.so.16
     22233:	find library=libxml2.so.2 [0]; searching
     22233:	  trying file=/opt/calibre/lib/libxml2.so.2
     22233:	  trying file=/lib/x86_64-linux-gnu/libxml2.so.2
     22233:	calling init: /lib/x86_64-linux-gnu/libxml2.so.2
RuntimeError: html5-parser and lxml are using different versions of libxml2. This happens commonly when using pip installed versions of lxml. Use pip install --no-binary lxml lxml instead. libxml2 versions: html5-parser: (2, 9, 14) != lxml: (2, 15, 0)
     22233:	calling fini: /lib/x86_64-linux-gnu/libxml2.so.2 [0]
     22233:	calling fini: /opt/calibre/lib/libxml2.so.16 [0]

Spoiler:

Code:

$ calibre-debug --gui
calibre 8.12  embedded-python: True
Linux-6.14.0-33-generic-x86_64-with-glibc2.39 Linux ('64bit', 'ELF')
('Linux', '6.14.0-33-generic', '#33~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Fri Sep 19 17:02:30 UTC 2')
Python 3.11.13
Interface language: None
EXE path: /opt/calibre/bin/calibre-debug
Successfully initialized third party plugins: ACSM Input (0, 1, 0) && Gather KFX-ZIP (from KFX Input) (2, 26, 2) && DeDRM (10, 0, 9) && Package KFX (from KFX Input) (2, 26, 2) && ACSM Input Plugin GUI Extension (0, 1, 0) && Baen (1, 1, 0) && Barnes & Noble (1, 5, 7) && Diaps Editing Toolbag (0, 5, 0) && EpubMerge (3, 2, 0) && EpubSplit (3, 12, 0) && Goodreads (1, 8, 3) && Hyphenate This! (0, 1, 3) && KFX metadata reader (from KFX Input) (2, 26, 2) && From KFX (2, 26, 2) && KFX Input (2, 26, 2) && KindleUnpack - The Plugin (0, 83, 8) && Kobo Utilities (2, 24, 3) && Modify ePub (1, 8, 6) && Quality Check (1, 14, 2)
QPA platform: xcb
devicePixelRatio: 1.09375
logicalDpi: 96.0 x 96.0
physicalDpi: 84.74714828897338 x 84.69527027027027
ApplicationPaletteChange event ignored
Using calibre Qt style: True
Traceback (most recent call last):
  File "runpy.py", line 198, in _run_module_as_main
  File "runpy.py", line 88, in _run_code
  File "site.py", line 47, in <module>
  File "site.py", line 43, in main
  File "calibre/debug.py", line 236, in main
  File "calibre/gui_launch.py", line 74, in calibre
  File "calibre/gui2/main.py", line 548, in main
  File "calibre/gui2/main.py", line 560, in run_main
  File "calibre/gui2/main.py", line 398, in run_gui
  File "calibre/gui2/main.py", line 408, in run_gui_
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/ui.py", line 51, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/init.py", line 37, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/library/alternate_views.py", line 67, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/pin_columns.py", line 9, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/library/delegates.py", line 46, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/dialogs/comments_dialog.py", line 11, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "calibre/gui2/comments_editor.py", line 14, in <module>
  File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
  File "bypy-importer.py", line 279, in exec_module
  File "html5_parser/__init__.py", line 31, in <module>
RuntimeError: html5-parser and lxml are using different versions of libxml2. This happens commonly when using pip installed versions of lxml. Use pip install --no-binary lxml lxml instead. libxml2 versions: html5-parser: (2, 9, 14) != lxml: (2, 15, 0)

Code:

$ calibre
ACSM Input: GUI Plugin Genesis!
qt.gui.imageio: libpng warning: iCCP: known incorrect sRGB profile
qt.gui.imageio: libpng warning: iCCP: known incorrect sRGB profile

bernie

kovidgoyal · 10-03-2025, 07:03 AM

That's just weird something is trying to load libxml.so.2 but nothing in calibre links against that. Maybe one of your calibre plugins? Try running it as

calibre-debug -g -- --ignore-plugins

In any case the workaround is simple just do

ln -s libxml2.so.16 /opt/calibre/lib/libxml2.so.2

that will force whatever it is to load libxml2.so.16

capink · 10-04-2025, 06:42 AM

Quote:

Originally Posted by kovidgoyal

That's just weird something is trying to load libxml.so.2 but nothing in calibre links against that. Maybe one of your calibre plugins? Try running it as

calibre-debug -g -- --ignore-plugins

In any case the workaround is simple just do

ln -s libxml2.so.16 /opt/calibre/lib/libxml2.so.2

that will force whatever it is to load libxml2.so.16

I was having the same problem upgrading from 7.23 to 8.12 on Ubuntu 24.04. The workaround posted above by Kovid solves the issue.

The --ignore-plugins does not make any difference. And the problem only happens when trying to start calibre in debug mode. Starting calibre normally was OK even before the workaround.

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09-27-2025, 01:12 AM	#2
kovidgoyal creator of calibre Posts: 45,631 Karma: 28549046 Join Date: Oct 2006 Location: Mumbai, India Device: Various	Doesn't reproduce for me. Are the env vars the same when you run calibre and calibre-debug --gui?

09-27-2025, 11:15 PM	#4
kovidgoyal creator of calibre Posts: 45,631 Karma: 28549046 Join Date: Oct 2006 Location: Mumbai, India Device: Various	Strange, dont see how that's possible. Try LD_DEBUG=libs ./calibre-debug -g 2>&1 \| grep libxml2 and post the output.

09-28-2025, 01:11 AM	#6
kovidgoyal creator of calibre Posts: 45,631 Karma: 28549046 Join Date: Oct 2006 Location: Mumbai, India Device: Various	Yeah I want the output from LD_DEBUG, that message doesnt tell me where the older libxml2 is coming from

09-28-2025, 02:47 AM	#8
kovidgoyal creator of calibre Posts: 45,631 Karma: 28549046 Join Date: Oct 2006 Location: Mumbai, India Device: Various	And what does ldd ./lib/calibre-extensions/html5_parser.html_parser.so output?

09-28-2025, 05:53 AM	#9
kovidgoyal creator of calibre Posts: 45,631 Karma: 28549046 Join Date: Oct 2006 Location: Mumbai, India Device: Various	I tried this in a debian:stable container which has libxml2.so.2.19.4 and couldnt reproduce there either.

09-28-2025, 07:36 PM	#11
gbm Wizard Posts: 2,216 Karma: 8888888 Join Date: Jun 2010 Device: Kobo Clara HD,Hisence Sero 7 Pro RIP, Nook STR, jetbook lite	Ok installed calibre 8 on a Mint 22.2 live usb and calibre debug worked. Will install on different disk or vm and test without and with the flatpacks I use. Will be tomorrow or Tuesday. bernie

09-29-2025, 12:14 AM	#12
kovidgoyal creator of calibre Posts: 45,631 Karma: 28549046 Join Date: Oct 2006 Location: Mumbai, India Device: Various	You need just grep libxml2 not grep libxml2 grep libxml And run the ldd comman inside the calibre installation dir, typically /opt/calibre

10-03-2025, 07:03 AM	#14
kovidgoyal creator of calibre Posts: 45,631 Karma: 28549046 Join Date: Oct 2006 Location: Mumbai, India Device: Various	That's just weird something is trying to load libxml.so.2 but nothing in calibre links against that. Maybe one of your calibre plugins? Try running it as calibre-debug -g -- --ignore-plugins In any case the workaround is simple just do ln -s libxml2.so.16 /opt/calibre/lib/libxml2.so.2 that will force whatever it is to load libxml2.so.16