diff --git a/static/index.html b/static/index.html
index 9cc638c2d..fab6a7f5a 100644
--- a/static/index.html
+++ b/static/index.html
@@ -3196,7 +3196,9 @@
                 <div class="text">
                   After completing a test, the theme will be set to a random
                   one. The random themes are not saved to your config. If set to
-                  'fav' only favourite themes will be randomized.
+                  'fav' only favourite themes will be randomized. The light and
+                  dark options allow you to randomize with themes that have
+                  light or dark backgrounds, respectively.
                 </div>
                 <div class="buttons">
                   <div