[JSWolf]

Originally Posted by kovidgoyal

Doesnt reproduce for me. DO you get any errors in the debug log?

I installed 8.99.5 and the bookshelf displayed. I went back to 8.99.6 with --ignore-plugins and the bookshelf displays.

It seems to be a plugin issue. Here is the debug log.

ApplicationPaletteChange event ignored
Using calibre Qt style: True
ApplicationPaletteChange event received
Traceback (most recent call last):
  File "calibre\gui2\ui.py", line 134, in __init__
  File "calibre\gui2\ui.py", line 152, in init_iaction
  File "calibre\customize\__init__.py", line 679, in load_actual_plugin
  File "importlib\__init__.py", line 88, in import_module
  File "<frozen importlib._bootstrap>", line 1398, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1371, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1342, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 938, in _load_unlocked
  File "calibre\customize\zipplugin.py", line 209, in exec_module
  File "calibre_plugins.annotations.action", line 11, in <module>
ModuleNotFoundError: No module named 'imp'
calibre_plugins.count_pages.statistics:415: SyntaxWarning: "\D" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\D"? A raw string is also an option.
calibre_plugins.count_pages.statistics:416: SyntaxWarning: "\D" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\D"? A raw string is also an option.
calibre_plugins.favourites_menu.common_menus:50: SyntaxWarning: "\g" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\g"? A raw string is also an option.
calibre_plugins.find_duplicates.common_menus:50: SyntaxWarning: "\g" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\g"? A raw string is also an option.
calibre_plugins.hyphenatethis.hyphenator.hutils:13: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.hyphenatethis.hyphenator.hutils:14: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.textdiff.main:722: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
EpubMerge: DEBUG: 2026-01-16 11:59:06,913: calibre_plugins.epubmerge.epubmerge_plugin(156): macmenuhack file_path:C:\Calibre Portable\Calibre Settings\plugins\fanficfare_macmenuhack.txt
calibre Debug log
calibre 8.99.6 Portable embedded-python: True
Windows-11-10.0.26200-SP0 Windows ('64bit', 'WindowsPE')
('Windows', '11', '10.0.26200')
Python 3.14.2
Windows: ('11', '10.0.26200', 'SP0', 'Multiprocessor Free')
Interface language: None
EXE path: C:\Calibre Portable\Calibre\calibre-debug.exe
Successfully initialized third party plugins: DeACSM (0, 0, 16) && Gather KFX-ZIP (from KFX Input) (2, 28, 0) && DeDRM (10, 0, 15) && Package KFX (from KFX Input) (2, 28, 0) && Annotations (1, 17, 13) && Apple Books covers (1, 1, 0) && Backup Configuration Folder (1, 1, 2) && Barnes & Noble (1, 5, 7) && BookFusion Plugin (0, 8, 1) && Count Pages (1, 14, 4) && Diaps Editing Toolbag (0, 5, 0) && EpubCheck (0, 2, 6) && EpubMerge (3, 2, 0) && EpubSplit (3, 12, 0) && Favourites Menu (1, 3, 1) && Find Duplicates (1, 10, 9) && Hyphenate This! (0, 1, 4) && KFX metadata reader (from KFX Input) (2, 28, 0) && From KFX (2, 28, 0) && KFX Input (2, 28, 0) && Set KFX metadata (from KFX Output) (2, 18, 0) && KFX Output (2, 18, 0) && Kindle hi-res covers (0, 5, 1) && KindleUnpack - The Plugin (0, 83, 8) && Kobo Metadata (1, 12, 0) && Kobo Utilities (2, 25, 0) && Modify ePub (1, 8, 8) && Quality Check (1, 14, 6) && Reading Goal (2, 0, 7) && Reading List (1, 15, 6) && ScrambleEbook (0, 6, 0) && StoryGraph (2, 0, 7) && TextDiff (1, 3, 1)
calibre 8.99.6 Portable embedded-python: True
Windows-11-10.0.26200-SP0 Windows ('64bit', 'WindowsPE')
('Windows', '11', '10.0.26200')
Python 3.14.2
Windows: ('11', '10.0.26200', 'SP0', 'Multiprocessor Free')
Interface language: None
EXE path: C:\Calibre Portable\Calibre\calibre-debug.exe
Successfully initialized third party plugins: DeACSM (0, 0, 16) && Gather KFX-ZIP (from KFX Input) (2, 28, 0) && DeDRM (10, 0, 15) && Package KFX (from KFX Input) (2, 28, 0) && Annotations (1, 17, 13) && Apple Books covers (1, 1, 0) && Backup Configuration Folder (1, 1, 2) && Barnes & Noble (1, 5, 7) && BookFusion Plugin (0, 8, 1) && Count Pages (1, 14, 4) && Diaps Editing Toolbag (0, 5, 0) && EpubCheck (0, 2, 6) && EpubMerge (3, 2, 0) && EpubSplit (3, 12, 0) && Favourites Menu (1, 3, 1) && Find Duplicates (1, 10, 9) && Hyphenate This! (0, 1, 4) && KFX metadata reader (from KFX Input) (2, 28, 0) && From KFX (2, 28, 0) && KFX Input (2, 28, 0) && Set KFX metadata (from KFX Output) (2, 18, 0) && KFX Output (2, 18, 0) && Kindle hi-res covers (0, 5, 1) && KindleUnpack - The Plugin (0, 83, 8) && Kobo Metadata (1, 12, 0) && Kobo Utilities (2, 25, 0) && Modify ePub (1, 8, 8) && Quality Check (1, 14, 6) && Reading Goal (2, 0, 7) && Reading List (1, 15, 6) && ScrambleEbook (0, 6, 0) && StoryGraph (2, 0, 7) && TextDiff (1, 3, 1)
QPA platform: windows
devicePixelRatio: 1.0
logicalDpi: 120.0 x 120.0
physicalDpi: 170.2198952879581 x 170.12093023255815
[0.00] Starting up...
[0.01] Showing splash screen...
[1.16] splash screen shown
[1.16] Initializing db...
[1.18] db initialized
[1.18] Constructing main UI...
[2.04] [DEBUG] [koboutilities.config:<module>:72] CreateNewCustomColumn is supported
qt.webengine.QWebEngineView OK
[5.38] [DEBUG] [koboutilities.action:KoboUtilitiesAction.genesis:117] Running in optimized mode
Textdiff: self.menu:
[5.87] GUI main window shown
[6.02] [DEBUG] [koboutilities.config:get_library_config:635] library_config: {
    "SchemaVersion": 1,
    "profiles": {},
    "readingPositionChangesStore": {
        "selectBooksInLibrary": false,
        "updeateGoodreadsProgress": false
    },
    "shelvesColumn": null
}
[6.02] [DEBUG] [koboutilities.action:KoboUtilitiesAction.device_driver_name:772] could not load extended driver. Exception= No module named 'calibre_plugins.kobotouch_extended'
[6.02] [DEBUG] [koboutilities.action:KoboUtilitiesAction.set_toolbar_button_tooltip:177] setting to text='Utilities to use with Kobo ereaders

Driver: KoboTouch'
[6.13] main UI initialized...
[6.13] Hiding splash screen
[6.13] splash screen hidden
[6.13] Started up in 6.13 seconds with 0 books
Exception in thread BookCaseLayout:
Traceback (most recent call last):
  File "threading.py", line 1082, in _bootstrap_inner
  File "threading.py", line 1024, in run
  File "calibre\gui2\library\bookshelf_view.py", line 1037, in layout_thread
  File "calibre\gui2\library\bookshelf_view.py", line 1065, in do_layout_in_worker
AttributeError: 'NoneType' object has no attribute 'strip'
Traceback (most recent call last):
  File "calibre\db\cache.py", line 3046, in close
  File "calibre_plugins.BackupConfigOnCalibreClose.__init__", line 39, in run
  File "calibre_plugins.BackupConfigOnCalibreClose.main", line 237, in run
  File "shutil.py", line 1238, in make_archive
  File "shutil.py", line 1113, in _make_zipfile
  File "zipfile\__init__.py", line 1986, in write
PermissionError: [Errno 13] Permission denied: 'C:\\Calibre Portable\\Calibre Settings\\caches\\qwe\\viewer-lookup\\sp\\Cookies'
stdout+stderr from file dialog helper: [b'', b'']
piped data from file dialog helper: [b"6\xfe\xa4\x91z,\xcd\x17>\xadE\xa5\xadE\xf6.2'\xfb\xa1^\xeb\x14\x1b\x06Wg\xe2& \xd2\x97", b'C:\\Calibre Portable\\Calibre Library\\Elizabeth2']
[130.27] [DEBUG] [koboutilities.config:get_library_config:635] library_config: {
    "SchemaVersion": 1,
    "currentReadingLocationColumn": "",
    "lastReadColumn": "",
    "precentReadColumn": "",
    "profiles": {},
    "ratingColumn": "",
    "readingPositionChangesStore": {
        "selectBooksInLibrary": false,
        "updeateGoodreadsProgress": false
    },
    "shelvesColumn": null
}
[130.27] [DEBUG] [koboutilities.action:KoboUtilitiesAction.device_driver_name:772] could not load extended driver. Exception= No module named 'calibre_plugins.kobotouch_extended'
[130.27] [DEBUG] [koboutilities.action:KoboUtilitiesAction.set_toolbar_button_tooltip:177] setting to text='Utilities to use with Kobo ereaders

Driver: KoboTouch'
[141.42] [Backup Configuration Folder]: starting backup process
Worker Launch took: 0.00 seconds
[216.31] Shutdown starting...
[216.34] Shutdown message shown...
[216.36] Grid view shutdown
[216.37] Bookshelf view shutdown
[216.37] Actions shutdown
[216.57] Various services shutdown
[216.57] Metadata backup shutdown
[216.57] [Backup Configuration Folder]: starting backup process
[222.40] Current database closed
[222.42] Windows hidden
[222.44] Waiting for overseers and live to shutdown
[222.44] Shutdown complete in 6.12, quitting...