Please read carefully the following terms if you use "Sage++ (Higmmer's Edition)" [this software]. To use this software, you must clearly understand and agree with these terms. If you don't agree, DO NOT USE this software.
You accept this software may contain known or unknown bugs, defects or vulnerabilities.
You understand possible threats caused by vulnerabilities of this software. (→Reference)
You know concretely how to protect yourself against vulnerabilities of this software. (→Reference)
You manage by yourself if you cannot get support, updates or fixes of this software due to some kind of situation.
You cope at your own risk with any kind of damages, losses or mental pains etc caused by using this software.
At first, uninstall the official Sage, Sage-Too, and its derivative software, or Sage++ 1.3.10 or less if you have already installed. You cannot overwrite-install because the GUID has been changed.(Your configurations will be kept as is(*))
Read the above Terms of Use, and click [Agree].
Click the appeared XPI file link.
If you meet the message: "Firefox prevented this site..." on the top notification bar, click [Allow].
Click [Install Now] in the "Software Install" dialog.
Restart Firefox to finish installation.
(*) Except for migration from the official Sage 1.4 or above.
** After installing successfully, you can update it automatically through auto-updating system on Firefox.