docs: Only show 2nd level headings in TOC

.nvim.lua

@@ -0,0 +1,14 @@
+-- https://github.com/hedyhli/markdown-toc.nvim
+--
+-- outline.nvim README uses markdown-toc to auto-update the ToC.
+-- The following config makes only second level headings be included.
+
+local ok, mtoc = pcall(require, 'mtoc')
+if ok then
+  mtoc.update_config({
+    headings = {
+      pattern = '^(##)%s+(.+)$',
+    }
+  })
+end
+

README.md

@@ -38,29 +38,14 @@ Table of contents
 * [Installation](#installation)
 * [Setup](#setup)
 * [Configuration](#configuration)
-  * [Terminology](#terminology)
-  * [Default options](#default-options)
-  * [Symbols table](#symbols-table)
 * [Commands](#commands)
 * [Default keymaps](#default-keymaps)
 * [Highlights](#highlights)
-  * [Outline window](#outline-window)
-  * [Preview window](#preview-window)
-  * [Other highlight groups](#other-highlight-groups)
 * [Lua API](#lua-api)
 * [Tips](#tips)
 * [Recipes](#recipes)
-  * [Unfold others](#unfold-others)
-  * [Auto-jump](#auto-jump)
-  * [Symbol details](#symbol-details)
-  * [Line numbers](#line-numbers)
-  * [Blend cursor with cursorline](#blend-cursor-with-cursorline)
-  * [Custom icons](#custom-icons)
-  * [Disable icons](#disable-icons)
 * [TODO](#todo)
 * [Limitations](#limitations)
-  * [Preview window](#preview-window-1)
-  * [Many outlines](#many-outlines)
 * [Related plugins](#related-plugins)
 
 <!-- mtoc-end -->