Add unstable thunderbird with home-manager

home/default.nix

@@ -1,6 +1,7 @@
 {
   lib,
   pkgs,
+  unstable,
   ...
 }: let
   hound-nvim = pkgs.vimUtils.buildVimPlugin {
@@ -444,6 +445,16 @@ in {
         ];
     };
 
+    thunderbird = {
+      enable = stdenv.isLinux;
+      package = unstable.thunderbird;
+      profiles = {
+        default = {
+          isDefault = true;
+        };
+      };
+    };
+
     firefox = {
       enable = stdenv.isLinux;