Log Message:
Sigil: update to 1.9.30.

Sigil-1.9.30
    Bug Fixes
      - fix Checkpointing to work with dulwich version 0.20.46+
      - fix css value parsing when !important is used
      - EmbeddedPython fixes to work with Python 3.11 and later (thank you sharkcz)
      - leave cursor position unchanged if nothing found when search groups of files
      - make all Numeric items in Reports align right
      - add support for thousands separator to Reports
      - allow blank dc:language values to prevent crashing (as Sigil-1.9.10 did)
      - allow unknown language codes to pass through MetaEditor
      - MetaEditor under epub2, allow custom opf scheme values
      - prevent duplicate spaces when reformatting CSS in import, charset and \ 
namespace
      - better prevent random OPF attribute order changes to simplify Checkpoint \ 
diffs
      - fixed file menu Print Preview for xhtml and image tabs
      - prevent plugins from crashing Sigil by deleting last xhtml file in epub
      - fix issue where images/css could not be properly added in an epub3 with \ 
no css files

    New Features
      - allow user to edit Checkpoint descriptions for clarity via Checkpoint menu
      - add ability to show the Checkpoint Change Log via Checkpoint menu
      - update to Hunspell 1.7.2 (released in December 2022) for spellchecking
      - update to latest zlib-1.2.13 for latest security fixes
      - move completely away from ever using OS system tmp folder for storing \ 
Sigil wip files
          instead create a new "workspace" folder inside Sigil \ 
Preferences folder
      - added ability to Print Preview and Print contents of Sigil's Preview window