HistoryBlock has been converted to WebExtension from the legacy XPCOM and completely rewritten using the new APIs. This should make feature releases more frequent moving forward.
Additionally, there are some new (and long-awaited) features to discuss:
1. New options page replaces the old clunky dialog. 2. Encryption method option - SHA1 (default and compliant with the previous version) and None (meaning plaintext blacklist items) 3. Matching method option - Domain (default and compliant with the previous version), Subdomain, and Full URL 4. Improved context menu (right-click) items - Block and Unblock