Enable backport repo in Debian Buster and configure for phpmyadmin install

install.sh

@@ -71,6 +71,20 @@ if [ "x$(which debconf-set-selections)" = "x" ]; then
   fi
 fi
 
+if [ "$(lsb_release -c -s)" == "buster" ]; then
+  if [ $( cat /etc/apt/sources.list /etc/apt/sources.list.d/*.list | sed 's|#.*||' | grep -c '^deb .* buster-backports' ) -lt 1 ]; then
+    echo -n 'Enabling Debian buster-backports repo for phpmyadmin...'
+    echo "deb http://deb.debian.org/debian buster-backports main" > /etc/apt/sources.list.d/enable_backports.list
+    echo ' ok'
+  fi
+  if [ ! -f /etc/apt/preferences.d/sympl-phpmyadmin ]; then
+    echo -n 'Enabling install of phpmyadmin from backports...'
+    echo -e "Package: phpmyadmin\nPin: release a=buster-backports\nPin-Priority: 900" > /etc/apt/preferences.d/sympl-phpmyadmin
+    echo -e "Package: php-twig\nPin: release a=buster-backports\nPin-Priority: 900" >> /etc/apt/preferences.d/sympl-phpmyadmin
+	echo ' ok'
+  fi
+fi
+
 echo "Installing Sympl from '$version' repository."
 
 echo "Setting defaults..."