According to the EmacsWiki: "redo.el is out-of-date and often destroys the contents of buffer because the behavior of ‘primitive-undo’ has been slightly different from old one since Emacs 22. redo+.el is a fork of redo.el and correctly works in newer version of Emacs."
# Ulrich Müller <ulm@gentoo.org> (17 May 2014) # Last upstream release in 1997, does not work reliably with # Emacs 22 and later. Use app-emacs/redo+ as replacement. # Masked for removal in 30 days, bug 510568. app-emacs/redo
Package removed.