diff --git a/dnsapi/dns_acmedns.sh b/dnsapi/dns_acmedns.sh
index b109a4e5..a21f8ef0 100755
--- a/dnsapi/dns_acmedns.sh
+++ b/dnsapi/dns_acmedns.sh
@@ -37,6 +37,16 @@ dns_acmedns_add() {
   ACMEDNS_PASSWORD="${ACMEDNS_PASSWORD:-$(_readdomainconf ACMEDNS_PASSWORD)}"
   ACMEDNS_SUBDOMAIN="${ACMEDNS_SUBDOMAIN:-$(_readdomainconf ACMEDNS_SUBDOMAIN)}"
 
+  #for compatibility: old versions stored ACMEDNS_UPDATE_URL in the account
+  #conf (issue 3899). Do not clear it here: it must stay available for the
+  #other domains that have not migrated to their domain conf yet.
+  if [ -z "$ACMEDNS_BASE_URL" ]; then
+    _acmedns_update_url="$(_readaccountconf_mutable ACMEDNS_UPDATE_URL)"
+    if [ "$_acmedns_update_url" ]; then
+      ACMEDNS_BASE_URL="$(echo "$_acmedns_update_url" | sed 's#/update$##')"
+    fi
+  fi
+
   if [ "$ACMEDNS_BASE_URL" = "" ]; then
     ACMEDNS_BASE_URL="https://auth.acme-dns.io"
   fi