added DooD mention

cli50.md

@@ -1,11 +1,11 @@
 # `cli50`
 
-`cli50` is a command-line tool via which you can (easily!) mount a directory within a container running [`cs50/cli`](cs50/cli), a Docker image based on Ubuntu 20.04, a popular distribution of Linux. We use `cli50` to work on CS50's own apps in a standard, contained environment, without having to install apps' dependencies on our own Macs and PCs. It provides a command-line environment similar, but not quite identical to, a terminal window on [CS50 IDE](ide/index).
+`cli50` is a command-line tool via which you can (easily!) mount a directory within a container running [`cs50/cli`](cs50/cli), a Docker image based on Ubuntu 22.04, a popular distribution of Linux. We use `cli50` to work on CS50's own apps in a standard, contained environment, without having to install apps' dependencies on our own Macs and PCs. It provides a command-line environment similar, but not quite identical to, a terminal window in [Visual Studio Code for CS50](cs50.dev). It also supports Docker outside of Docker (DooD).
 
 ## Installation
 
 1. Install [Docker](/docker), if you haven't already.
-1. Install [Python 3.6](/python) or later, if you haven't already.
+1. Install [Python 3.8](/python) or later, if you haven't already.
 1. Install [`pip`](/pip), if you haven't already.
 1. Install `cli50` itself:
     ```text