Developer Mode

What it does

 * You can right-click in the game window and access the Chromium developer toolbar. This helps for editing CSS.
 * Various data editors can be accessed from the main menu, including the Dialogue Editor.
 * It notices if you edit files while it's running. This makes it run noticeably slower.

How to turn it on

 * Right clicking on the game in your Steam library and going to Properties
 * Click on Set Launch Options in the General tab
 * Enter  into the box.
 * You can turn it off again by deleting it out of the box.
 * If you're on Itch, you can write a batch file to pass  as an option.