I like TextEdit because it is a simple RTF editor that yet offers a number of cool word processing features. Only one thing that it doesn't have is one of those "distraction free" modes where not only do you work full screen, but you also have nice margins around the screen.
Well, it was trivial enough to emulate that with TextEdit itself, I wonder why it took me so long to figure it out.
- View > Enter Full Screen
- Format > Wrap to Window
- File > Page Setup...
- in Paper Sizes, select Manage Custom Sizes
- Create your own big paper size.
That's pretty much it.
The problem is that the "window" size is constrained by the paper size you choose for printing. So you just need to create a paper size that fills your screen:
My "Grand Écran" size is 450 x 5,000 mm with 0 mm margins.
You can create a System Service with a shortcut by using AppleScript and Automator to switch any TextEdit page into this mode, or revert to a "normal" mode, or just manually select the paper size when you start a new document, or even use it as your default paper size... Et voilà!