diff --git a/portal/assets/themes/unsplash/custom_portal.css b/portal/assets/themes/unsplash/custom_portal.css
index 331714a..3a02d9d 100644
--- a/portal/assets/themes/unsplash/custom_portal.css
+++ b/portal/assets/themes/unsplash/custom_portal.css
@@ -1,7 +1,9 @@
 /*
 ===============================================================================
- This file contain extra CSS rules to customize the YunoHost user portal and
- can be used to customize app tiles, buttons, etc...
+   Unsplash themes for SSOWat's backgrounds
+
+   WARNING: external images are queried from Unsplash API every time, which
+   makes this theme not suitable for off-the-internet clients...
 ===============================================================================
 */
 
@@ -22,6 +24,7 @@ body {
 }
 
 .ynh-user-portal {
+  /* If image is not yielded, fall back on traditional grey 'normal' background*/
   background-image: url('https://source.unsplash.com/random/featured/?nature') !important;
   background-repeat: no-repeat;
   background-size: cover;
diff --git a/portal/assets/themes/unsplash/custom_portal.js b/portal/assets/themes/unsplash/custom_portal.js
deleted file mode 100644
index 80c27bd..0000000
--- a/portal/assets/themes/unsplash/custom_portal.js
+++ /dev/null
@@ -1,33 +0,0 @@
-/*
-===============================================================================
- This JS file may be used to customize the YunoHost user portal *and* also
- will be loaded in all app pages if the app nginx's conf does include the
- appropriate snippet.
-
- You can monkeypatch init_portal (loading of the user portal) and
- init_portal_button_and_overlay (loading of the button and overlay...) to do
- custom stuff
-===============================================================================
-*/
-
-/*
- * Monkeypatch init_portal to customize the app tile style
- *
-init_portal_original = init_portal;
-init_portal = function()
-{
-    init_portal_original();
-    // Some stuff here
-}
-*/
-
-/*
- * Monkey patching example to do custom stuff when loading inside an app
- *
-init_portal_button_and_overlay_original = init_portal_button_and_overlay;
-init_portal_button_and_overlay = function()
-{
-    init_portal_button_and_overlay_original();
-    // Custom stuff to do when loading inside an app
-}
-*/