[Quoth]

Just gives error

calibre, version 3.45.2
ERROR: Unhandled exception: <b>TypeError</b>:unsupported operand type(s) for *: 'NoneType' and 'int'

calibre 3.45.2  embedded-python: True is64bit: True
Linux-4.15.0-54-generic-x86_64-with-debian-stretch-sid Linux ('64bit', 'ELF')
('Linux', '4.15.0-54-generic', '#58~16.04.1-Ubuntu SMP Mon Jun 24 13:21:41 UTC 2019')
Python 2.7.15
Linux: ('debian', 'stretch/sid', '')
Interface language: None
Successfully initialized third party plugins: Gather KFX-ZIP (from KFX Input) (1, 17, 1) && DeDRM (6, 6, 1) && K4PC, K4Mac, Kindle Mobi and Topaz DeDRM (0, 3, 1) && Package KFX (from KFX Input) (1, 17, 1) && KePub Input (3, 0, 0) && Library Splitter (1, 0, 1) && KePub Metadata Reader (3, 0, 2) && Quick Preferences (1, 4, 1) && Amazon.com Multiple Countries (1, 0, 0) && Quality Check (1, 9, 11) && EpubSplit (2, 7, 0) && Author Book Count (2, 1, 6) && Wiki Reader (2, 1, 0) && Reading List (1, 6, 6) && Kobo Utilities (2, 8, 0) && Find Duplicates (1, 6, 3) && EpubCheck (0, 1, 8) && Goodreads (1, 4, 0) && Open With (1, 5, 10) && Modify ePub (1, 3, 13) && Generate Cover (1, 5, 21) && KindleUnpack - The Plugin (0, 81, 5) && KePub Output (3, 1, 3) && Smashwords Metadata (1, 0, 0) && FictionDB (1, 2, 0) && Annotations (1, 9, 2) && Obok DeDRM (6, 5, 4) && Manage Series (1, 2, 8) && Resize Cover (1, 0, 2) && Kobo Books (1, 7, 0) && KePub Metadata Writer (3, 0, 3) && Manage Sony x50 Reader Book List (1, 2, 11) && Hyphenate This! (0, 0, 8) && KoboTouchExtended (3, 1, 5) && X-Ray Creator (3, 2, 1) && Barnes & Noble (1, 2, 15) && KFX metadata reader (from KFX Input) (1, 17, 1) && KFX Input (1, 17, 1) && Media File Importer (1, 0, 21) && Kindle Collections (1, 7, 24) && EpubMerge (2, 5, 0) && Kindle hi-res covers (0, 4, 0) && Kindle covers (G) (0, 3, 0) && Copy Cover To Device (2, 0, 0) && Extract ISBN (1, 4, 4)
Traceback (most recent call last):
  File "calibre_plugins.koboutilities.action", line 1906, in getAnnotationForSelected
  File "calibre_plugins.koboutilities.action", line 2644, in _getAnnotationForSelected
  File "site-packages/calibre/devices/kobo/driver.py", line 1191, in get_annotations
  File "site-packages/calibre/devices/kobo/bookmark.py", line 30, in __init__
  File "site-packages/calibre/devices/kobo/bookmark.py", line 94, in get_bookmark_data
TypeError: unsupported operand type(s) for *: 'NoneType' and 'int'