A blog style introduction to cartman-mutt is available and includes some more rationale for its existence.
You can find latest code on gitlab
These instructions assume you're on a debian-derivate unix system
git clone https://github.com/tamentis/cartman.git cd cartman sudo python setup.py install
git clone https://gitlab.com/strk/cartman-mutt.git cd cartman-mutt sudo make install sudo make install-systemwide-rc
Open a trac-notification email in the Mutt pager, and press:
^tc-- to comment the ticket
^to-- to open the ticket in the browser
?in the pager would show the available keystrokes for reference. The cartman-mutt ones all start with
^t(mnemonic: "control trac").