diff --git a/data/hooks/backup/18-data_multimedia b/data/hooks/backup/18-data_multimedia
new file mode 100644
index 000000000..f80cff0b3
--- /dev/null
+++ b/data/hooks/backup/18-data_multimedia
@@ -0,0 +1,17 @@
+#!/bin/bash
+
+# Exit hook on subcommand error or unset variable
+set -eu
+
+# Source YNH helpers
+source /usr/share/yunohost/helpers
+
+# Backup destination
+backup_dir="${1}/data/multimedia"
+
+if [ -e "/home/yunohost.multimedia/.nobackup" ]; then
+    exit 0
+fi
+
+# Backup multimedia directory
+ynh_backup --src_path="/home/yunohost.multimedia" --dest_path="${backup_dir}" --is_big --not_mandatory
diff --git a/data/hooks/restore/18-data_multimedia b/data/hooks/restore/18-data_multimedia
new file mode 100644
index 000000000..eb8ef2608
--- /dev/null
+++ b/data/hooks/restore/18-data_multimedia
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+# Exit hook on subcommand error or unset variable
+set -eu
+
+# Source YNH helpers
+source /usr/share/yunohost/helpers
+
+ynh_restore_file --origin_path="/home/yunohost.multimedia" --not_mandatory
diff --git a/data/templates/mysql/my.cnf b/data/templates/mysql/my.cnf
index 429596cf5..3da4377e1 100644
--- a/data/templates/mysql/my.cnf
+++ b/data/templates/mysql/my.cnf
@@ -30,7 +30,7 @@ skip-external-locking
 key_buffer_size = 16K
 max_allowed_packet = 16M
 table_open_cache = 4
-sort_buffer_size = 256K
+sort_buffer_size = 4M
 read_buffer_size = 256K
 read_rnd_buffer_size = 256K
 net_buffer_length = 2K
diff --git a/debian/changelog b/debian/changelog
index 48f3bbdca..a1e7c8f83 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,19 @@
+yunohost (4.2.8.3) stable; urgency=low
+
+  - [fix] mysql: Another bump for sort_buffer_size to make Nextcloud 22 work (34e9246b)
+
+  Thanks to all contributors <3 ! (ljf (zamentur))
+
+ -- Kay0u <pierre@kayou.io>  Fri, 10 Sep 2021 10:40:38 +0200
+
+yunohost (4.2.8.2) stable; urgency=low
+
+  - [fix] mysql: Bump sort_buffer_size to 256K to fix Nextcloud 22 installation (d8c49619)
+
+  Thanks to all contributors <3 ! (ericg)
+
+ -- Alexandre Aubin <alex.aubin@mailoo.org>  Tue, 07 Sep 2021 23:23:18 +0200
+
 yunohost (4.2.8.1) stable; urgency=low
 
   - [fix] Safer location for slapd backup during hdb/mdb migration (3c646b3d)