diff --git a/README.md b/README.md
index 7a7743d..56ab32d 100644
--- a/README.md
+++ b/README.md
@@ -38,6 +38,7 @@
 
 1. [Create a `chrome` folder](https://www.userchrome.org/how-create-userchrome-css.html) in your Zen Browser's profile directory.
 2. Copy the `userChrome.css`, `userContent.css`, and `zen-logo.svg` files of your preferred theme from the [`themes/`](themes/) directory in this repository to your `chrome` folder.
+3. Enable `toolkit.legacyUserProfileCustomizations.stylesheets` in [about:config](about:config).
 
 > [!NOTE]
 > If you're using the [🌻 Latte](themes/Latte/) theme, set your browser to light mode. For [🪴 Frappé](themes/Frappe/), [🌺 Macchiato](themes/Macchiato/), or [🌿 Mocha](themes/Mocha/), enable dark mode to apply the theme correctly.