Calibre 6.9.0
New features

E-book viewer: When exporting highlights as plain text include titles from chapters at all levels not just the first level.
Edit book: Reports: Show the number of words per file in the Files section of the report
Windows builds: sign DLLs in addition to EXEs to make Microsoft’s new “Smart App Control” tool happy.
Sending by email: When adding comments also add series.
Nook driver: Put files in NOOK/Books instead of NOOK/My Files on recent nook devices so they are all listed in one place in the NOOK UI. Closes tickets: 1990730
calibredb list: Allow using a template as one of the returned fields.
Tag browser: Add context menu action to turn on/off sub-categorization for a category
Bug fixes

Merging books: Fix title sort not being updated when the title is updated. Closes tickets: 1996802
Content server viewer: Fix incorrect sorting of highlights in the same paragraph.
Content server viewer: When exporting highlights as text include chapter titles.
Improve rendering of the separator handle dots introduced in the previous release.
Edit book: Fix regression in previous release causing applying any container update marking all open image editors as modified.
Fix a regression in the previous release that caused copying book details to clipboard to use unix line endings on windows.
Improved news sources

Bloomberg
The Globe and Mail
Spectator Magazine
The New York Times
The Hindu
MIT Technology Review