feat: add pageTitleFormatter config (#2695)

Author: sy-records

docs/configuration.md

@@ -275,6 +275,24 @@ window.$docsify = {
 };
 ```
 
+## pageTitleFormatter
+
+- Type: `Function`
+- Default: `null`
+
+Optional function to customize how the site `name` is used when composing the document title. If provided, Docsify will call this function with the configured `name` (which may contain HTML) and use the returned string as the title portion for the site name — Docsify will not automatically strip HTML or otherwise modify the value. If not provided, Docsify falls back to the default behavior of stripping HTML tags from `name`.
+
+Basic example — strip HTML and trim (equivalent to Docsify's default behavior):
+
+```js
+window.$docsify = {
+  name: '<span>My Site</span>',
+  pageTitleFormatter(name) {
+    return name ? name.replace(/<[^>]+>/g, '').trim() : '';
+  },
+};
+```
+
 ## hideSidebar
 
 - Type : `Boolean`
@@ -456,7 +474,7 @@ window.$docsify = {
 
 ## name
 
-- Type: `Boolean | String`
+- Type: `Boolean|String`
 
 Website name as it appears in the sidebar.
 

src/core/config.js

@@ -27,6 +27,7 @@ const defaultDocsifyConfig = () => ({
   fallbackLanguages: /** @type {null | string[]} */ (null),
   fallbackDefaultLanguage: '',
   formatUpdated: /** @type {string | ((updatedAt: string) => string)} */ (''),
+  pageTitleFormatter: /** @type {null | ((name: string) => string)} */ (null),
   /** For the frontmatter plugin. */
   frontMatter: /** @type {Record<string, TODO> | null} */ (null),
   hideSidebar: false,

src/core/event/index.js

@@ -323,13 +323,21 @@ export function Events(Base) {
      * @void
      */
     onRender() {
-      const { name } = this.config;
+      const { name, pageTitleFormatter } = this.config;
       const currentPath = this.router.toURL(this.router.getCurrentPath());
       const currentSection = dom
         .find(`.sidebar a[href='${currentPath}']`)
         ?.getAttribute('title');
 
-      const plainName = name ? name.replace(/<[^>]+>/g, '').trim() : name;
+      // If a pageTitleFormatter is provided, let the user format the name
+      // (no automatic HTML stripping). Otherwise, default to stripping
+      // HTML tags from the configured name.
+      const plainName =
+        typeof pageTitleFormatter === 'function' && typeof name === 'string'
+          ? pageTitleFormatter(name)
+          : name
+            ? name.replace(/<[^>]+>/g, '').trim()
+            : name;
       const currentTitle = plainName
         ? currentSection
           ? `${currentSection} - ${plainName}`