Opens split-screen editor in PageKit

From what I can see in your screenshots:

1. First image (the small icon)

   • It appears to be the “Split View” or “Split Screen” toggle icon in the PageKit editor’s toolbar. It’s typically represented by a small bracket/arrow shape indicating a side-by-side view.

2. Second image

   • This shows the PageKit editor interface with an arrow pointing to that same icon in the top-right area (near “Preview”). Clicking this icon opens a split-screen editor mode, which lets you see the raw HTML (or Markdown, depending on your setup) on one side and a live preview on the other.

So, if you’re using PageKit’s built-in editor and want to see both your source content and its rendered output at the same time, you can click that icon. It should switch the editor into a two-column layout:

• Left side: Your editable text/HTML.
• Right side: The preview of how it will look once rendered.

This is especially helpful when you’re working with HTML, Markdown, or shortcodes, as you can instantly see how your changes appear without manually toggling back and forth between edit and preview modes.