luckybackup is a powerful, fast and reliable backup & sync tool that
relies on rsync. It is written and maintained by Loukas Avgeriou.
The program has a graphical frontend as well as a commandline
frontend.

Web links in 'About' won't connect when luckyBackup is run as root.

Inline documentation: Gui -> Help -> luckyBackup Handbook (F1) 
    External links give a blank page that stalls the manual; to 
    continue with inline documentation, restart the program.
Online documentation: https://luckybackup.sourceforge.net/manual.html

The current version, 0.5.0, has not changed for years, but the author
still provides support; see
    Discussions: https://sourceforge.net/p/luckybackup/discussion/
    Known bugs: https://luckybackup.sourceforge.net/bugs.html

Note, issues with lucky backup could relate to (updates of) rsync.
