Added note on Debian/Ubuntu

Author: Kalle Fagerberg

src/content/docs/setup/install.mdx

@@ -163,6 +163,16 @@ chmod 644 ~/.kube/config
 
 :::
 
+## Debian/Ubuntu
+
+[![Debian version](https://repology.org/badge/version-for-repo/debian_unstable/kubecolor.svg)](https://repology.org/project/kubecolor/versions)
+
+The Debian package (and its dervivatives like Ubuntu, elementary OS,
+Linux Mint, Pop!_OS, Zorin OS, etc) is very outdated and as such is
+highly discouraged.
+
+Please use a different mode for installing kubecolor.
+
 ## Missing a repository?
 
 We only add new repositories and ways to install kubecolor on demand.