Backup menu style

src/freedombone-controlpanel

 function menu_backup_restore {
     while true
     do
-        data=$(mktemp 2>/dev/null)
-        dialog --backtitle $"Freedombone Control Panel" \
-               --title $"Backup and Restore" \
-               --radiolist $"Choose an operation:" 19 70 12 \
-               1 $"Backup data to USB drive" off \
-               2 $"Restore GPG key from USB keydrive" off \
-               3 $"Restore data from USB drive" off \
-               4 $"Reinstall mariadb" off \
-               5 $"Configure remote backups" off \
-               6 $"Restore from remote backup" off \
-               7 $"Backup GPG key to USB (master keydrive)" off \
-               8 $"Backup GPG key to USB (fragment keydrive)" off \
-               9 $"Format a USB drive (LUKS encrypted)" off \
-               10 $"Remove backups from a USB drive" off \
-               11 $"Back to main menu" on 2> "$data"
-        sel=$?
-        case $sel in
-            1) rm -f "$data"
-               break;;
-            255) rm -f "$data"
-                 break;;
-        esac
-        case $(cat "$data") in
+        W=(1 $"Backup data to USB drive"
+           2 $"Restore GPG key from USB keydrive"
+           3 $"Restore data from USB drive"
+           4 $"Reinstall mariadb"
+           5 $"Configure remote backups"
+           6 $"Restore from remote backup"
+           7 $"Backup GPG key to USB (master keydrive)"
+           8 $"Backup GPG key to USB (fragment keydrive)"
+           9 $"Format a USB drive (LUKS encrypted)"
+           10 $"Remove backups from a USB drive")
+
+        # shellcheck disable=SC2068
+        selection=$(dialog --backtitle $"Freedombone Administrator Control Panel" --title $"Backup and Restore" --menu $"Choose an operation, or ESC for main menu:" 19 70 12 "${W[@]}" 3>&2 2>&1 1>&3)
+
+        if [ ! "$selection" ]; then
+           break
+        fi
+
+        case $selection in
             1) backup_data;;
             2) restore_gpg_key;;
             3) restore_data;;
             8) create_keydrive_fragment;;
             9) format_drive;;
             10) remove_backups;;
-            11) rm -f "$data"
-                break;;
         esac
-        rm -f "$data"
     done
 }
 
         # shellcheck disable=SC2068
         selection=$(dialog --backtitle $"Freedombone Administrator Control Panel" --title $"Email Menu" --menu $"Choose an operation, or ESC for main menu:" 15 70 8 "${W[@]}" 3>&2 2>&1 1>&3)
 
+        if [ ! "$selection" ]; then
+           break
+        fi
+
         case $selection in
             1) add_to_mailing_list;;
             2) remove_user_from_mailing_list;;
         # shellcheck disable=SC2068
         selection=$(dialog --backtitle $"Freedombone Administrator Control Panel" --title $"Domain or User Blocking" --menu $"Choose an operation, or ESC for main menu:" 13 70 6 "${W[@]}" 3>&2 2>&1 1>&3)
 
+        if [ ! "$selection" ]; then
+           break
+        fi
+
         case $selection in
             1) domain_blocking_add;;
             2) domain_blocking_remove;;