docs: Add user guide for *Make a public stream private* feature

templates/zerver/help/change-stream-accessibility.md

@@ -0,0 +1,95 @@
+# Change the accessibility of a stream
+
+If you are a Zulip realm administrator, you can change who can join your stream
+by changing the stream's accessibility.
+
+Please note that any users that were previously subscribed to the stream will
+remain subscribed to the stream after you change the stream's accesibility.
+
+## Make a public stream private
+
+1. Click the cog (![cog](/static/images/help/cog.png)) next to **Streams** in
+the left sidebar. A tooltip labeled **Subscribe, add, or configure streams**
+will appear upon hovering above the cog.
+
+    ![Browse streams](/static/images/help/streams-1.png)
+
+2. The stream browser will now appear, showing all streams that you've subscribed
+to by default. If you wish to see streams that you aren't subscribed to, click
+the **All Streams** tab; the tab will turn gray upon doing so.
+
+    ![All streams](/static/images/help/all-streams.png)
+
+3. Locate the public stream that you want to make private in the stream browser.
+You can search for specific streams by entering the name of the stream in the
+**Filter streams** search box.
+
+    ![Filter streams box](/static/images/help/filter-stream.png)
+
+4. Click on the stream that you want to make private. The right side of the
+stream browser, labeled **Stream Settings**, will now display the settings of
+the stream that you've selected.
+
+    ![Stream selected](/static/images/help/stream-selected.png)
+
+5. After making sure that your cursor is hovering over the **Stream Settings**
+section (right half of the stream browser), scroll down to the **Administrator settings**
+section. This section shows all stream settings that can be modified
+by a realm administrator.
+
+    ![Stream administrator settings](/static/images/help/stream-admin-settings.png)
+
+6. To make a public stream private, simply locate the red **Make stream private**
+button located on the bottom of the **Administrator settings** section and click
+on it.
+
+7. After clicking the **Make stream private** button, the button will turn into
+a blue **Make stream public** button, a green section labeled
+**The stream has been made private!** will appear, and the stream's icon will
+switch from a **#** to a lock icon, confirming that the stream has been made private.
+
+    ![Public stream private success](/static/images/help/public-stream-private-success.png)
+
+## Make a private stream public
+
+1. Click the cog (![cog](/static/images/help/cog.png)) next to **Streams** in
+the left sidebar. A tooltip labeled **Subscribe, add, or configure streams**
+will appear upon hovering above the cog.
+
+    ![Browse streams](/static/images/help/streams-1.png)
+
+2. The stream browser will now appear, showing all streams that you've subscribed
+to by default. If you wish to see streams that you aren't subscribed to, click
+the **All Streams** tab; the tab will turn gray upon doing so.
+
+    ![All streams](/static/images/help/all-streams.png)
+
+3. Locate the public stream that you want to make public in the stream browser.
+You can search for specific streams by entering the name of the stream in the
+**Filter streams** search box.
+
+    ![Filter streams box](/static/images/help/filter-stream.png)
+
+4. Click on the stream that you want to make public. The right side of the
+stream browser, labeled **Stream Settings**, will now display the settings of
+the stream that you've selected.
+
+    ![Stream selected](/static/images/help/stream-settings-private.png)
+
+5. After making sure that your cursor is hovering over the **Stream Settings**
+section (right half of the stream browser), scroll down to the **Administrator settings**
+section. This section shows all stream settings that can be modified
+by a realm administrator.
+
+    ![Stream administrator settings](/static/images/help/stream-admin-settings-private.png)
+
+6. To make a public stream private, simply locate the blue **Make stream public**
+button located on the bottom of the **Administrator settings** section and click
+on it.
+
+7. After clicking the **Make stream public** button, the button will turn into
+a red **Make stream private** button, a green section labeled
+**The stream has been made public!** will appear, and the stream's icon will
+change from a lock to a **#** icon, confirming that the stream has been made public.
+
+    ![Public stream private success](/static/images/help/private-stream-public.png)

templates/zerver/help/index.md

@@ -93,7 +93,7 @@ as a “**realm**”.
 * [Rename a stream](/help/rename-stream)
 * Preview a stream (not implemented)
 * [Unsubscribe from a stream](/help/unsubscribe-stream)
-* Change who can join a stream
+* [Change who can join a stream](/help/change-stream-accessibility)
 * [Pin a stream](/help/pin-a-stream)
 * [Change the color of a stream](/help/change-stream-color)
 * Message a stream by email
@@ -151,7 +151,7 @@ as a “**realm**”.
 * Set default streams for new users
 * [Rename a stream](/help/rename-stream)
 * Change a stream's description
-* Make a public stream private
+* [Make a public stream private](/help/change-stream-accessibility#make-a-public-stream-private)
 * Add or remove users from a stream
 
 ---