diff --git a/_machines/notebook01.yml b/_machines/notebook01.yml
index 4c356a1..2d59a1a 100644
--- a/_machines/notebook01.yml
+++ b/_machines/notebook01.yml
@@ -10,6 +10,7 @@ users:
   vt: 1
   firefox_profiles:
     - name: lu9k8ywl.default
+      manage_css: false
 
 screen:
   1: eDP-1
diff --git a/_machines/tb-hak.yml b/_machines/tb-hak.yml
index 01df39a..4747297 100644
--- a/_machines/tb-hak.yml
+++ b/_machines/tb-hak.yml
@@ -11,6 +11,7 @@ users:
   vt: 1
   firefox_profiles:
     - name: 3wmp9hdb.default-1565075150057
+      manage_css: true
 - name: hannes-private
   group: tpp
   vt: 2
diff --git a/user.yml b/user.yml
index d715901..a2b973c 100644
--- a/user.yml
+++ b/user.yml
@@ -301,7 +301,7 @@
       #sidebar {
         width: 400px !important;
       }
-  with_items: "{{ user.firefox_profiles }}"
-  when: user.firefox_profiles is defined
+  when: item.manage_css
+  with_items: "{{ user.firefox_profiles | default [] }}"
   tags:
     - firefox