From the drop-down list, select how the editor will be shown by default: both editor and preview panes, editor only, or preview only pane.
Select this checkbox to automatically scroll from the cursor position in the source code to the respective position in the preview.
Select this checkbox to use grayscale for rendering.
Load from URI
Specify here the path to the desired .css file. Click to find the file in question in the file system.
Add CSS rules
Type a particular CSS to be used for rendering the preview. For example, you can specify here the background color and font weight.