Mailspring

Npackd itself and also all data about packages (but not the package binaries or associated icons) is licensed under GPLv3
Windows is a registered trademark of Microsoft Corporation in the United States and other countries.
GLYPHICONS FREE were used and are released under the Creative Commons Attribution 3.0 Unported License (CC BY 3.0)
Bootstrap was used and is released under MIT License
jQuery CookieBar Plugin was used and is released under the Creative Commons Attribution 3.0 Unported License (CC BY 3.0)