Add instructions for backing up and restoring logos

These docs can be removed once a fix for
freedomofpress/securedrop#5868
is included in a production release.

docs/backup_and_restore.rst

@@ -104,6 +104,30 @@ archive in the output of the backup command.
 
 .. include:: includes/backup-warning.txt
 
+.. _backing_up_logos:
+
+Backing up your custom logo
+'''''''''''''''''''''''''''
+
+As of SecureDrop |version|, the backup will not include any custom logo file
+that you may have configured for your SecureDrop instance. To back up the logo,
+download it using Tor Browser or on the command line. From ``~/Persistent``
+(a level above the ``securedrop`` directory), the following command will
+download a custom logo for a SecureDrop instance that uses v3 onion services:
+
+.. code:: sh
+
+   wget $(cat securedrop/install_files/ansible-base/app-sourcev3-ths)/static/i/custom_logo.png
+
+For a v2-only instance, the command is:
+
+.. code:: sh
+
+   wget $(cat securedrop/install_files/ansible-base/app-source-ths)/static/i/custom_logo.png
+
+If you get a 404 error, that most likely means that you are using the default
+SecureDrop logo.
+
 Restoring from a Backup
 -----------------------
 
@@ -334,6 +358,8 @@ Migrating Using a V2+V3 or V3-Only Backup
 #. :doc:`Test the new instance <test_the_installation>` to verify that the
    web interfaces are available and the servers can be reached via SSH.
 
+#. If you had previously configured a custom logo for your SecureDrop instance,
+   :ref:`upload it again <Updating Logo Image>` using the *Admin Interface*.
 
 .. _migrate_v2:
 
@@ -469,6 +495,9 @@ source accounts, and journalist accounts. To do so, follow the steps below:
    The new instance's onion service addresses will be unchanged, but the
    old instance's data and accounts will now be available.
 
+#. If you had previously configured a custom logo for your SecureDrop instance,
+   :ref:`upload it again <Updating Logo Image>` using the *Admin Interface*.
+
 .. _additional_restore_info:
 
 Additional Information

docs/upgrade/focal_migration.rst

@@ -209,8 +209,11 @@ you have completed the :ref:`preparatory steps <focal_prep>`.
    services will be removed as part of this migration.
 #. Announce your maintenance window. As part of this procedure, your servers
    will become unreachable.
-#. :doc:`Take a backup of the current instance <../backup_and_restore>`. Once
-   you have taken a backup of the servers, power them off.
+#. :doc:`Take a backup of the current instance <../backup_and_restore>`.
+   If you have configured a custom logo for your SecureDrop instance, make
+   sure to :ref:`download it <backing_up_logos>` as well.
+
+   Once you have taken a backup of the servers, power them off.
 
    .. warning::