Sigil 1.5.1

Sigil

Sigil is a free, open source, multi-platform ebook editor. It is designed to edit books in ePub format (both ePub 2 and ePub 3). It also provides features for advanced users, like direct XHTML, CSS and XPGT editing. You can use it to add any of the metadata entries supported by the EPUB specification and create a hierarchical Table of Contents.

Sigil key features:

Free and open source software under GPLv3
Multi-platform: runs on Windows, Mac, and Linux (note Linux only receives limited support)
Full UTF-16 support
EPUB 2 spec support with limited EPUB 3 support
Multiple Views: Book View, Code View and Preview View
WYSIWYG editing in Book View
Complete control over directly editing EPUB syntax in Code View
Table of Contents generator with multi-level heading support
Metadata editor
User interface translated into many languages
Spell checking with default and user configurable dictionaries
Full Regular Expression (PCRE) support for Find & Replace
Supports import of EPUB and HTML files, images, and style sheets,
Documents can be validated for EPUB compliance with the integrated
All imported files have their formatting corrected, and your editing can be optionally cleaned
Plugins!

Sigil 1.5.1 features:

Can now handle single xhtml file sizes over 2megabytes in size via its own URL Schemehandler
Will now highlight matched open close tag pairs while editing in Code View
Delete open close tag pairs (Remove Tag Pair)
Default selection of text for basic CodeView formatting including bold, italic, etc based on cursor position
Shift double-click (and Alt double-click) on a tag to select tag contents (including tag)
Expanded split on Sigil Split Marker capabilities to work better with nested tags
Added a new C++ CSS Parser and Query engine that works with Sigil's version of Gumbo
The Reports tool for "CSS Selectors" now lists all CSS selectors not just classes
The "Delete Unused Styles" tool now handles all unused CSS Selectors not just classes
The Reports for "CSS Selectors" and "Delete Unused Selectors" now handle selectors in XHTML Style tags
Added ability to load text and csv files to Group Saved Searches to automate lists of replacements
Reworked the Metadata Editor to be much more Human Readable with tooltips to show xml tags
Added semantic code to the descriptive field in Add Semantics as a learning aid (Thank You BeckyEbook!)
Checkpoint ManageRepos now has the ability to sort the repo table by any column (Thank You BeckyEbook!)
The Sigil User Guide has be completely reworked to bring it to Sigil 1.5.0+ levels

Bug Fixes:

Fix issue with custom ncx names in non-standard empty epub layouts
Fix Import Text to properly add ncx if missing for epub2
Fix issue with "Delete Unused Styles" not properly detecting all used selectors
Fix issues with repeated use of Mend and Prettify on bare text in structural tags
Fix extra line issue with Link to Stylesheet (Thank you BeckyEBook!)
Fix bug in id assignment in EPUB3 Metadata editor
Fix bug in trailing slash in Move To Folder paths
Fix bug in spelling of Columbia->Colombia in Languages (Thank you Tex2002ans!)
Fix bug in Clip Editor pasting of multiple clips
Fix bug in PerformCSSUpdates related to quoted string in content: values
Fix bug related to iframe handling when loading Preview
Fix typos in XMLEntities descriptions (Thank you BeckEbook!)
Fix numeric table alignment to align right in multiple tables (Thank you BeckyEbook!)
Fix bug in Add Existing not properly using QProgressDialog for long import
Removed long deprecated and now invalid use of "altlang" in EPUB3 Metadata Editor