Zen "mode" / configuration

[tobimensch]

This feature request is inspired by vscode's zen mode. There zen mode means, that only the editor windows/panes remain visible, while all UI elements become hidden. For example no statusbar, no sidepanels, no line numbers, basically nothing that eats away at the size of the editor views.

This could be implemented as a toggle command: :zen

When untoggling zen mode it should restore all the settings (ie. line numbers if any), like they were before zen mode got enabled.

In zen mode the ex command line should only come into view, when and only when, you're in ex command mode.

One of the main features of zen mode is that the code takes up the whole space from top to bottom, with no distractive UI elements.

In vscode zen mode also goes into fullscreen. This is tough to imitate in a terminal application, of course. But there is a way to do it in X11, by setting the FULLSCREEN property of the X11 window, which isn't a cross platform solution, but I'd still like to see it.

Purpose: Go into distraction free programming mode (toggle zen mode), then do some undistracted programming, then go back to normal mode (untoggle zen mode).

Zen mode isn't really a vim mode in the same way as normal mode or insert mode are. It's more of a temporary UI configuration.

One problem is how to indicate the currently active vim mode while there's no statusbar shown:

• Cursor indicates mode.
  • Block cursor => normal mode
  • Slim cursor => insert mode
  • Blinking cursor => replace mode
• Show notification of vim mode change for ie. 2 seconds at top-right or bottom-right corner

Also the statusbar should be blended in and out, when something is to be shown on it. For example when using the ga command in normal mode to view information on the current character, this information is usually shown on the statusbar. So the statusbar should be activated when using a command that "does something" with the statusbar. And on the next key input the statusbar should disappear again (because we're in distraction free mode/zen mode).