diff --git a/README.md b/README.md
index d7c10ee..ef56996 100644
--- a/README.md
+++ b/README.md
@@ -13,19 +13,21 @@ This project is early in development and users are encouraged to open issues or
 
 0. Enable the default dark theme (Tools > Add-ons > Theme > Dark)
 
+1. Set `toolkit.legacyUserProfileCustomizations.stylesheets` to `true` in the Config Editor (![hamburger menu](https://design.firefox.com/icons/icons/desktop/menu-16.svg) → ![Gear](https://design.firefox.com/icons/icons/desktop/preferences-16.svg) Preferences → End of page, at the bottom)
+
 1. Download this repository and rename the folder to `chrome`.
 
-2. Place the `chrome` folder inside your Thunderbird profile directory. To find your profile directory, you can do the following from within Thunderbird:
+1. Place the `chrome` folder inside your Thunderbird profile directory. To find your profile directory, you can do the following from within Thunderbird:
 
 	- Help > Troubleshooting Information > Application Basics section > Profile Folder > Show in Finder
 
-3. (Optional) To change the background and text area of the message composition pages, you can dd the following lines to your `user.js` file within the profile directory (this will not alter the appearance of sent messages):
-
-```js
-user_pref("browser.display.foreground_color", "#b1b1b3");
-user_pref("browser.display.background_color", "#38383d");
-```
+1. (Optional) To change the background and text area of the message composition pages, you can dd the following lines to your `user.js` file within the profile directory (this will not alter the appearance of sent messages):
 
-The `user.js` does not exist be default; you will have to create the file (name and case sensitive) if you haven't done so in the past. 
+	```js
+	user_pref("browser.display.foreground_color", "#b1b1b3");
+	user_pref("browser.display.background_color", "#38383d");
+ 	```
+	
+	The `user.js` does not exist be default; you will have to create the file (name and case sensitive) if you haven't done so in the past. 
 
-4. Restart Thunderbird
+1. Restart Thunderbird