diff --git a/bin/tests/system/isctest/vars/features.py b/bin/tests/system/isctest/vars/features.py
index d5c3a92417..985b830466 100644
--- a/bin/tests/system/isctest/vars/features.py
+++ b/bin/tests/system/isctest/vars/features.py
@@ -18,7 +18,6 @@ from .basic import BASIC_VARS
 FEATURES = {
     "DNSRPS": "--enable-dnsrps",
     "DNSTAP": "--enable-dnstap",
-    "EXTENDED_DS_DIGEST": "--extended-ds-digest",
     "FIPS_DH": "--have-fips-dh",
     "FIPS_MODE": "--have-fips-mode",
     "FIPS_PROVIDER": "--fips-provider",