chore: prepare v2.0.0-beta.16 release (#6760)

website/versioned_docs/version-2.0.0-beta.16/guides/docs/sidebar/multiple-sidebars.md

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+---
+slug: /sidebar/multiple-sidebars
+---
+
+# Using multiple sidebars
+
+You can create a sidebar for each **set of Markdown files** that you want to **group together**.
+
+:::tip
+
+The Docusaurus site is a good example of using multiple sidebars:
+
+- [Docs](../../../introduction.md)
+- [API](../../../cli.md)
+
+:::
+
+Consider this example:
+
+```js title="sidebars.js"
+module.exports = {
+  tutorialSidebar: {
+    'Category A': ['doc1', 'doc2'],
+  },
+  apiSidebar: ['doc3', 'doc4'],
+};
+```
+
+When browsing `doc1` or `doc2`, the `tutorialSidebar` will be displayed; when browsing `doc3` or `doc4`, the `apiSidebar` will be displayed.
+
+## Understanding sidebar association {#sidebar-association}
+
+Following the example above, if a `commonDoc` is included in both sidebars:
+
+```js title="sidebars.js"
+module.exports = {
+  tutorialSidebar: {
+    'Category A': ['doc1', 'doc2', 'commonDoc'],
+  },
+  apiSidebar: ['doc3', 'doc4', 'commonDoc'],
+};
+```
+
+How does Docusaurus know which sidebar to display when browsing `commonDoc`? Answer: it doesn't, and we don't guarantee which sidebar it will pick.
+
+When you add doc Y to sidebar X, it creates a two-way binding: sidebar X contains a link to doc Y, and when browsing doc Y, sidebar X will be displayed. But sometimes, we want to break either implicit binding:
+
+1. _How do I generate a link to doc Y in sidebar X without making sidebar X displayed on Y?_ For example, when I include doc Y in multiple sidebars as in the example above, and I want to explicitly tell Docusaurus to display one sidebar?
+2. _How do I make sidebar X displayed when browsing doc Y, but sidebar X shouldn't contain the link to Y?_ For example, when Y is a "doc home page" and the sidebar is purely used for navigation?
+
+Front matter option `displayed_sidebar` will forcibly set the sidebar association. For the same example, you can still use doc shorthands without any special configuration:
+
+```js title="sidebars.js"
+module.exports = {
+  tutorialSidebar: {
+    'Category A': ['doc1', 'doc2'],
+  },
+  apiSidebar: ['doc3', 'doc4'],
+};
+```
+
+And then add a front matter:
+
+```md title="commonDoc.md"
+---
+displayed_sidebar: apiSidebar
+---
+```
+
+Which explicitly tells Docusaurus to display `apiSidebar` when browsing `commonDoc`. Using the same method, you can make sidebar X which doesn't contain doc Y appear on doc Y:
+
+```md title="home.md"
+---
+displayed_sidebar: tutorialSidebar
+---
+```
+
+Even when `tutorialSidebar` doesn't contain a link to `home`, it will still be displayed when viewing `home`.
+
+If you set `displayed_sidebar: null`, no sidebar will be displayed whatsoever on this page, and subsequently, no pagination either.
+
+## Generating pagination {#generating-pagination}
+
+Docusaurus uses the sidebar to generate the "next" and "previous" pagination links at the bottom of each doc page. It strictly uses the sidebar that is displayed: if no sidebar is associated, it doesn't generate pagination either. However, the docs linked as "next" and "previous" are not guaranteed to display the same sidebar: they are included in this sidebar, but in their front matter, they may have a different `displayed_sidebar`.
+
+If a sidebar is displayed by setting `displayed_sidebar` front matter, and this sidebar doesn't contain the doc itself, no pagination is displayed.
+
+You can customize pagination with front matter `pagination_next` and `pagination_prev`. Consider this sidebar:
+
+```js title="sidebars.js"
+module.exports = {
+  tutorial: [
+    'introduction',
+    {
+      installation: ['windows', 'linux', 'macos'],
+    },
+    'getting-started',
+  ],
+};
+```
+
+The pagination next link on "windows" points to "linux", but that doesn't make sense: you would want readers to proceed to "getting started" after installation. In this case, you can set the pagination manually:
+
+```md title="windows.md"
+---
+# highlight-next-line
+pagination_next: getting-started
+---
+
+# Installation on Windows
+```
+
+You can also disable displaying a pagination link with `pagination_next: null` or `pagination_prev: null`.
+
+The pagination label by default is the sidebar label. You can use the front matter `pagination_label` to customize how this doc appears in the pagination.
+
+## The `ref` item {#sidebar-item-ref}
+
+The `ref` type is identical to the [`doc` type](#sidebar-item-doc) in every way, except that it doesn't participate in generating navigation metadata. It only registers itself as a link. When [generating pagination](#generating-pagination) and [displaying sidebar](#sidebar-association), `ref` items are completely ignored.
+
+Consider this example:
+
+```js title="sidebars.js"
+module.exports = {
+  tutorialSidebar: {
+    'Category A': [
+      'doc1',
+      'doc2',
+      // highlight-next-line
+      {type: 'ref', id: 'commonDoc'},
+      'doc5',
+    ],
+  },
+  apiSidebar: ['doc3', 'doc4', 'commonDoc'],
+};
+}
+```
+
+You can think of the `ref` type as the equivalent to doing the following:
+
+- Setting `displayed_sidebar: tutorialSidebar` for `commonDoc` (`ref` is ignored in sidebar association)
+- Setting `pagination_next: doc5` for `doc2` and setting `pagination_prev: doc2` for `doc5` (`ref` is ignored in pagination generation)