From b3159b14b8d8dce0ddd93e1e8c0753f13112b3d7 Mon Sep 17 00:00:00 2001
From: Luffy <52o@qq52o.cn>
Date: Thu, 24 Jul 2025 18:04:40 +0800
Subject: [PATCH 1/2] refactor: simplify auto header insertion logic

- Use querySelector instead of getElementsByTagName for clarity
- Avoid redundant DOM wrapping by directly accessing firstElementChild
- Add null check to prevent potential DOM insertion errors
---
 src/core/render/index.js | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/core/render/index.js b/src/core/render/index.js
index 3ee35513b..85b6e7200 100644
--- a/src/core/render/index.js
+++ b/src/core/render/index.js
@@ -342,11 +342,15 @@ export function Render(Base) {
 
       if (autoHeader && activeEl) {
         const main = dom.getNode('#main');
-        const firstNode = main.children[0];
-        if (firstNode && firstNode.tagName !== 'H1') {
-          const h1 = this.compiler.header(activeEl.innerText, 1);
-          const wrapper = dom.create('div', h1);
-          dom.before(main, wrapper.children[0]);
+        const hasH1 = main.querySelector('h1');
+
+        if (!hasH1) {
+          const h1HTML = this.compiler.header(activeEl.innerText, 1);
+          const h1Node = dom.create('div', h1HTML).firstElementChild;
+
+          if (h1Node) {
+            dom.before(main, h1Node);
+          }
         }
       }
     }

From f969a655048d09eff740e27f4412184dcb62849f Mon Sep 17 00:00:00 2001
From: Luffy <52o@qq52o.cn>
Date: Wed, 30 Jul 2025 11:00:53 +0800
Subject: [PATCH 2/2] docs: update autoHeader

---
 docs/configuration.md | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/docs/configuration.md b/docs/configuration.md
index f1fbce04a..bb5df138c 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -72,7 +72,9 @@ window.$docsify = {
 - Type: `Boolean`
 - Default: `false`
 
-If `loadSidebar` and `autoHeader` are both enabled, for each link in `_sidebar.md`, prepend a header to the page before converting it to HTML. See [#78](https://github.com/docsifyjs/docsify/issues/78).
+If `loadSidebar` and `autoHeader` are both enabled, for each link in `_sidebar.md`, prepend a header to the page before converting it to HTML — but only if the page does not already contain an H1 heading.
+
+For more details, see [#78](https://github.com/docsifyjs/docsify/issues/78).
 
 ```js
 window.$docsify = {