Tested against Debian Buster, confirmed working.

meta/main.yml

@@ -1,3 +1,5 @@
+---
+
 galaxy_info:
   author: Xan Manning
   description: Ansible role for installing k3s as either a standalone server or cluster
@@ -38,6 +40,7 @@ galaxy_info:
         - 7
     - name: Debian
       versions:
+        - buster
         - jessie
         - stretch
     - name: Ubuntu
@@ -47,10 +50,12 @@ galaxy_info:
 
   galaxy_tags:
     - k3s
+    - k8s
     - kubernetes
     - docker
     - containerd
     - cluster
+    - rancher
     # List tags for your role here, one per line. A tag is a keyword that describes
     # and categorizes the role. Users find roles by searching for tags. Be sure to
     # remove the '[]' above, if you add tags to this list.

tests/Vagrantfile

@@ -41,7 +41,7 @@ Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
   end
 
   config.vm.define "node2" do |node2|
-    node2.vm.box = "debian/stretch64"
+    node2.vm.box = "debian/buster64"
     node2.vm.hostname = "k3s-node02"
     node2.vm.network "private_network", ip: "172.16.3.31"
     node2.vm.provider "virtualbox" do |vb|