Add extension policies

modules/firefox.nix

@@ -4,6 +4,20 @@
   programs.firefox = {
     enable = true;
     
+    # Policies to configure extension behavior
+    policies = {
+      ExtensionSettings = {
+        # Pin uBlock Origin to toolbar
+        "uBlock0@raymondhill.net" = {
+          default_area = "navbar";
+        };
+        # Pin Linkding Extension to toolbar
+        "{61a05c39-ad45-4086-946f-32adb0a40a9d}" = {
+          default_area = "navbar";
+        };
+      };
+    };
+    
     profiles.yanlin = {
       id = 0;
       isDefault = true;