fix colorModeToggle_ selector

Author: slorber

website/src/css/customTheme.scss

@@ -5,6 +5,11 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+/* TODO remove after v3.8 upgrade */
+div[class*="colorModeToggle_"] {
+  visibility: hidden;
+}
+
 @import "shared";
 
 :root {