Added documentation for sticky navigation tabs

docs/insiders.md

@@ -125,7 +125,8 @@ for MkDocs Insiders. You can click on each feature to learn more about it:
 - [x] [Search suggestions help to save keystrokes][14]
 - [x] [Highlighting of matched search terms in content area][15]
 - [x] Search goes to first result on ++enter++ (I'm feeling lucky)
-- [x] [Navigation can be grouped into sections][16]
+- [x] [Navigation tabs can be made sticky][23]
+- [x] [Navigation can be grouped into sections][17]
 - [x] [Navigation can be always expanded][17]
 - [x] [Navigation and table of contents can be hidden][18]
 - [x] [Table of contents can be integrated into navigation][19]
@@ -144,14 +145,15 @@ for MkDocs Insiders. You can click on each feature to learn more about it:
   [20]: setup/setting-up-the-header.md#automatic-hiding
   [21]: reference/admonitions.md#inline-blocks
   [22]: setup/changing-the-language.md#site-language-selector
+  [23]: setup/setting-up-navigation.md#sticky-navigation-tabs
 
 ## Roadmap
 
 The following list of funding goals – named after varieties of chili peppers 
-[I'm growing on my balcony][23] – shows which features are already available
+[I'm growing on my balcony][24] – shows which features are already available
 in Material for MkDocs Insiders.
 
-  [23]: https://www.instagram.com/squidfunk/
+  [24]: https://www.instagram.com/squidfunk/
 
 ### Madame Jeanette
 
@@ -208,6 +210,7 @@ in Material for MkDocs Insiders.
 [:octicons-flame-24: Funding goal: __$3,000__][6] ·
 :octicons-lock-24: Status: _Insiders only_
 
+- [x] [Navigation tabs can be made sticky][23]
 - [x] [Remove _Made with Material for MkDocs_ from footer][11]
 - [ ] Brand-new and exclusive vertical layout
 
@@ -224,10 +227,10 @@ improvements (e.g. search) do not require any changes to existing configuration.
 This means that your users will be able to build the docs locally with the
 regular version and when they push their changes to CI/CD, they will be built
 with Material for MkDocs Insiders. For this reason, it's recommended to
-[install Insiders][24] only in CI, as you don't want to expose your `GH_TOKEN`
+[install Insiders][25] only in CI, as you don't want to expose your `GH_TOKEN`
 to users.
 
-  [24]: publishing-your-site.md#github-pages
+  [25]: publishing-your-site.md#github-pages
 
 ### Terms
 
@@ -237,7 +240,7 @@ terms?_
 
 Yes. Whether you're an individual or a company, you may use _Material for MkDocs
 Insiders_ precisely under the same terms as Material for MkDocs, which are given
-by the [MIT license][25]. However, we kindly ask you to respect the following
+by the [MIT license][26]. However, we kindly ask you to respect the following
 guidelines:
 
 - Please __don't distribute the source code__ from Material for MkDocs Insiders.
@@ -248,7 +251,7 @@ guidelines:
 - If you cancel your subscription, you're removed as a collaborator and will
   miss out on future updates of Material for MkDocs Insiders. However, you may
   __use the latest version__ that's available to you __as long as you like__.
-  Just remember that __[GitHub deletes private forks][26]__.
+  Just remember that __[GitHub deletes private forks][27]__.
 
-  [25]: license.md
+  [26]: license.md
-  [26]: https://docs.github.com/en/github/setting-up-and-managing-your-github-user-account/removing-a-collaborator-from-a-personal-repository
+  [27]: https://docs.github.com/en/github/setting-up-and-managing-your-github-user-account/removing-a-collaborator-from-a-personal-repository

docs/setup/setting-up-navigation.md

@@ -111,6 +111,36 @@ navigation is plausible on mobile devices. As another example, see the
   [9]: https://www.mkdocs.org/user-guide/configuration/#nav
   [10]: https://github.com/squidfunk/mkdocs-material/blob/master/mkdocs.yml
 
+#### Sticky navigation tabs
+
+[:octicons-file-code-24: Source][11] ·
+:octicons-unlock-24: Feature flag ·
+:octicons-beaker-24: Experimental ·
+[:octicons-heart-fill-24:{: .tx-heart } Insiders only][11]{: .tx-insiders }
+
+When _sticky tabs_ are enabled, navigation tabs will lock below the header and
+always remain visible when scrolling down. Just add the following two feature
+flags to `mkdocs.yml`:
+
+``` yaml
+theme:
+  features:
+    - navigation.tabs
+    - navigation.tabs.sticky
+```
+
+=== "With sticky tabs"
+
+    [![With sticky tabs][12]][12]
+
+=== "Without sticky tabs"
+
+    [![Without sticky tabs][13]][13]
+
+  [11]: ../insiders.md
+  [12]: ../assets/screenshots/navigation-tabs-sticky.png
+  [13]: ../assets/screenshots/navigation-tabs-collapsed.png
+
 ### Navigation sections
 
 [:octicons-file-code-24: Source][11] ·
@@ -129,14 +159,13 @@ theme:
 
 === "With sections"
 
-    [![With sections][12]][12]
+    [![With sections][14]][14]
 
 === "Without sections"
 
     [![Without sections][8]][8]
 
-  [11]: ../insiders.md
+  [14]: ../assets/screenshots/navigation-sections.png
-  [12]: ../assets/screenshots/navigation-sections.png
 
 Both feature flags, _tabs_ and _sections_, can be combined with each other. If
 both feature flags are enabled, sections are rendered for 2nd level navigation
@@ -160,19 +189,19 @@ theme:
 
 === "With expansion"
 
-    [![With expansion][13]][13]
+    [![With expansion][15]][15]
 
 === "Without expansion"
 
     [![Without expansion][8]][8]
 
-  [13]: ../assets/screenshots/navigation-expand.png
+  [15]: ../assets/screenshots/navigation-expand.png
 
 ### Table of contents
 
-[:octicons-file-code-24: Source][14] · [:octicons-workflow-24: Extension][15]
+[:octicons-file-code-24: Source][16] · [:octicons-workflow-24: Extension][17]
 
-The [Table of contents][16] extension, which is part of the standard Markdown
+The [Table of contents][18] extension, which is part of the standard Markdown
 library, provides some options that are supported by Material for MkDocs to
 customize its appearance:
 
@@ -204,7 +233,7 @@ customize its appearance:
 :   :octicons-milestone-24: Default: `headerid.slugify` – This option allows for 
     customization of the slug function. For some languages, the default may not
     produce good and readable identifiers. Consider using another slug function
-    like for example those from [Python Markdown Extensions][17]:
+    like for example those from [Python Markdown Extensions][19]:
 
     === "Unicode"
 
@@ -245,21 +274,21 @@ customize its appearance:
               toc_depth: 0
         ```
 
-    Note that MkDocs will not generate [anchor links][18] for levels outside
+    Note that MkDocs will not generate [anchor links][20] for levels outside
     the range defined with `toc_depth`. However, Material for MkDocs also allows
-    to [hide the table of contents][19] on a specific page while keeping
+    to [hide the table of contents][21] on a specific page while keeping
     permalinks.
 
 _Material for MkDocs doesn't provide official support for the other options of
 this extension, so they may be supported but can also yield weird results. Use
 them at your own risk._
 
-  [14]: https://github.com/squidfunk/mkdocs-material/blob/master/src/partials/toc.html
+  [16]: https://github.com/squidfunk/mkdocs-material/blob/master/src/partials/toc.html
-  [15]: https://python-markdown.github.io/extensions/toc/
+  [17]: https://python-markdown.github.io/extensions/toc/
-  [16]: https://python-markdown.github.io/extensions/toc/#usage
+  [18]: https://python-markdown.github.io/extensions/toc/#usage
-  [17]: https://facelessuser.github.io/pymdown-extensions/extras/slugs/
+  [19]: https://facelessuser.github.io/pymdown-extensions/extras/slugs/
-  [18]: #permalink
+  [20]: #permalink
-  [19]: #hide-the-sidebars
+  [21]: #hide-the-sidebars
 
 #### Navigation integration
 
@@ -279,13 +308,13 @@ theme:
 
 === "Integrate table of contents"
 
-    [![Integrate table of contents][20]][20]
+    [![Integrate table of contents][22]][22]
 
 === "Separate table of contents"
 
     [![Separate table of contents][8]][8]
 
-  [20]: ../assets/screenshots/toc-integrate.png
+  [22]: ../assets/screenshots/toc-integrate.png
 
 The content section will now always stretch to the right side, resulting in
 more space for your content. This feature flag can be combined with all other
@@ -298,7 +327,7 @@ feature flags, e.g. [tabs][1] and [sections][2].
 
 Sometimes it's desirable to hide the navigation and/or table of contents
 sidebar, especially when there's a single navigation item. This can be done for
-any page using the [Metadata][21] extension:
+any page using the [Metadata][23] extension:
 
 ``` yaml
 ---
@@ -312,26 +341,26 @@ hide:
 
 === "Hide navigation"
 
-    [![Hide navigation][22]][22]
+    [![Hide navigation][24]][24]
 
 === "Hide table of contents"
 
-    [![Hide table of contents][23]][23]
+    [![Hide table of contents][25]][25]
 
 === "Hide both"
 
-    [![Hide navigation and table of contents][24]][24]
+    [![Hide navigation and table of contents][26]][26]
 
-  [21]: ../../reference/meta-tags/#metadata
+  [23]: ../../reference/meta-tags/#metadata
-  [22]: ../assets/screenshots/hide-navigation.png
+  [24]: ../assets/screenshots/hide-navigation.png
-  [23]: ../assets/screenshots/hide-toc.png
+  [25]: ../assets/screenshots/hide-toc.png
-  [24]: ../assets/screenshots/hide-navigation-toc.png
+  [26]: ../assets/screenshots/hide-navigation-toc.png
 
 ## Customization
 
 ### Keyboard shortcuts
 
-[:octicons-file-code-24: Source][25] ·
+[:octicons-file-code-24: Source][27] ·
 :octicons-mortar-board-24: Difficulty: _easy_
 
 Material for MkDocs includes several keyboard shortcuts that make it possible
@@ -357,7 +386,7 @@ to navigate your project documentation via keyboard. There're two modes:
     * ++n++ , ++period++ : go to next page
 
 Let's say you want to bind some action to the ++x++ key. By using [additional
-JavaScript][26], you can subscribe to the `keyboard$` observable and attach
+JavaScript][28], you can subscribe to the `keyboard$` observable and attach
 your custom event listener:
 
 ``` js
@@ -373,12 +402,12 @@ The call to `#!js key.claim()` will essentially execute `#!js preventDefault()`
 on the underlying event, so the keypress will not propagate further and touch
 other event listeners.
 
-  [25]: https://github.com/squidfunk/mkdocs-material/blob/master/src/assets/javascripts/integrations/keyboard/index.ts
+  [27]: https://github.com/squidfunk/mkdocs-material/blob/master/src/assets/javascripts/integrations/keyboard/index.ts
-  [26]: ../customization.md#additional-javascript
+  [28]: ../customization.md#additional-javascript
 
 ### Content area width
 
-[:octicons-file-code-24: Source][27] ·
+[:octicons-file-code-24: Source][29] ·
 :octicons-mortar-board-24: Difficulty: _easy_
 
 The width of the content area is set so the length of each line doesn't exceed
@@ -387,7 +416,7 @@ is a reasonable default, as longer lines tend to be harder to read, it may be
 desirable to increase the overall width of the content area, or even make it
 stretch to the entire available space.
 
-This can easily be achieved with an [additional stylesheet][28] and a few lines
+This can easily be achieved with an [additional stylesheet][30] and a few lines
 of CSS:
 
 === "Increase width"
@@ -406,5 +435,5 @@ of CSS:
     }
     ```
 
-  [27]: https://github.com/squidfunk/mkdocs-material/blob/aeaa00a625abf952f355164de02c539b061e6127/src/assets/stylesheets/main/layout/_base.scss#L99-L104
+  [29]: https://github.com/squidfunk/mkdocs-material/blob/aeaa00a625abf952f355164de02c539b061e6127/src/assets/stylesheets/main/layout/_base.scss#L99-L104
-  [28]: ../customization.md#additional-css
+  [30]: ../customization.md#additional-css