diff --git a/controllers/testdata/appconfig-expected/deploy.yaml b/controllers/testdata/appconfig-expected/deploy.yaml
index 924875cf..e8394aa4 100644
--- a/controllers/testdata/appconfig-expected/deploy.yaml
+++ b/controllers/testdata/appconfig-expected/deploy.yaml
@@ -6,5 +6,5 @@ spec:
   template:
     spec:
       containers:
-      - name: hello
-        image: helloworld:1.0.1 # SETTER_SITE
+        - name: hello
+          image: helloworld:1.0.1 # SETTER_SITE
diff --git a/controllers/testdata/appconfig-expected2/deploy.yaml b/controllers/testdata/appconfig-expected2/deploy.yaml
index 136c05a4..b5ee0daf 100644
--- a/controllers/testdata/appconfig-expected2/deploy.yaml
+++ b/controllers/testdata/appconfig-expected2/deploy.yaml
@@ -6,5 +6,5 @@ spec:
   template:
     spec:
       containers:
-      - name: hello
-        image: helloworld:1.2.0 # SETTER_SITE
+        - name: hello
+          image: helloworld:1.2.0 # SETTER_SITE
diff --git a/controllers/testdata/appconfig-setters-expected/deploy.yaml b/controllers/testdata/appconfig-setters-expected/deploy.yaml
index 924875cf..e8394aa4 100644
--- a/controllers/testdata/appconfig-setters-expected/deploy.yaml
+++ b/controllers/testdata/appconfig-setters-expected/deploy.yaml
@@ -6,5 +6,5 @@ spec:
   template:
     spec:
       containers:
-      - name: hello
-        image: helloworld:1.0.1 # SETTER_SITE
+        - name: hello
+          image: helloworld:1.0.1 # SETTER_SITE
diff --git a/go.mod b/go.mod
index 16441c5d..38c2d3d6 100644
--- a/go.mod
+++ b/go.mod
@@ -31,12 +31,9 @@ require (
 	k8s.io/client-go v0.20.4
 	k8s.io/kube-openapi v0.0.0-20210421082810-95288971da7e
 	sigs.k8s.io/controller-runtime v0.8.3
-	sigs.k8s.io/kustomize/kyaml v0.10.19
+	sigs.k8s.io/kustomize/kyaml v0.10.21
 )
 
-// Force downgrade to version used by kyaml.
-replace gopkg.in/yaml.v3 => gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c
-
 // side-effect of depending on source-controller
 // required by https://github.com/helm/helm/blob/v3.5.2/go.mod
 replace (
diff --git a/go.sum b/go.sum
index cc0626a2..f2b806bf 100644
--- a/go.sum
+++ b/go.sum
@@ -449,7 +449,6 @@ github.com/go-toolsmith/typep v1.0.2/go.mod h1:JSQCQMUPdRlMZFswiq3TGpNp1GMktqkR2
 github.com/go-xmlfmt/xmlfmt v0.0.0-20191208150333-d5b6f63a941b/go.mod h1:aUCEOzzezBEjDBbFBoSiya/gduyIiWYRP6CnSFIV8AM=
 github.com/gobuffalo/envy v1.7.0/go.mod h1:n7DRkBerg/aorDM8kbduw5dN3oXGswK5liaSCx4T5NI=
 github.com/gobuffalo/envy v1.7.1/go.mod h1:FurDp9+EDPE4aIUS3ZLyD+7/9fpx7YRt/ukY6jIHf0w=
-github.com/gobuffalo/here v0.6.0/go.mod h1:wAG085dHOYqUpf+Ap+WOdrPTp5IYcDAs/x7PLa8Y5fM=
 github.com/gobuffalo/logger v1.0.1/go.mod h1:2zbswyIUa45I+c+FLXuWl9zSWEiVuthsk8ze5s8JvPs=
 github.com/gobuffalo/packd v0.3.0/go.mod h1:zC7QkmNkYVGKPw4tHpBQ+ml7W/3tIebgeo1b36chA3Q=
 github.com/gobuffalo/packr/v2 v2.7.1/go.mod h1:qYEvAazPaVxy7Y7KR0W8qYEE+RymX74kETFqjFoFlOc=
@@ -717,7 +716,6 @@ github.com/mailru/easyjson v0.0.0-20190626092158-b2ccc519800e/go.mod h1:C1wdFJiN
 github.com/mailru/easyjson v0.7.0 h1:aizVhC/NAAcKWb+5QsU1iNOZb4Yws5UO2I+aIprQITM=
 github.com/mailru/easyjson v0.7.0/go.mod h1:KAzv3t3aY1NaHWoQz1+4F1ccyAH66Jk7yos7ldAVICs=
 github.com/maratori/testpackage v1.0.1/go.mod h1:ddKdw+XG0Phzhx8BFDTKgpWP4i7MpApTE5fXSKAqwDU=
-github.com/markbates/pkger v0.17.1/go.mod h1:0JoVlrol20BSywW79rN3kdFFsE5xYM+rSCQDXbLhiuI=
 github.com/marstr/guid v1.1.0/go.mod h1:74gB1z2wpxxInTG6yaqA7KrtM0NZ+RbrcqDvYHefzho=
 github.com/matoous/godox v0.0.0-20190911065817-5d6d842e92eb/go.mod h1:1BELzlh859Sh1c6+90blK8lbYy0kwQf1bYlBhBysy1s=
 github.com/matryer/is v1.2.0 h1:92UTHpy8CDwaJ08GqLDzhhuixiBUUD1p3AU6PHddz4A=
@@ -1523,8 +1521,9 @@ gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 h1:tQIYjPdBoyREyB9XMu+nnTclpTYkz2zFM+lzLJFO4gQ=
+gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gotest.tools v2.2.0+incompatible/go.mod h1:DsYFclhRJ6vuDpmuTbkuFWG+y2sxOXAzmJt81HFBacw=
 gotest.tools/v3 v3.0.2/go.mod h1:3SzNCllyD9/Y+b5r9JIKQ474KzkZyqLqEfYqMsX94Bk=
 gotest.tools/v3 v3.0.3/go.mod h1:Z7Lb0S5l+klDB31fvDQX8ss/FlKDxtlFlw3Oa8Ymbl8=
@@ -1630,8 +1629,8 @@ sigs.k8s.io/controller-runtime v0.8.3 h1:GMHvzjTmaWHQB8HadW+dIvBoJuLvZObYJ5YoZru
 sigs.k8s.io/controller-runtime v0.8.3/go.mod h1:U/l+DUopBc1ecfRZ5aviA9JDmGFQKvLf5YkZNx2e0sU=
 sigs.k8s.io/kustomize v2.0.3+incompatible h1:JUufWFNlI44MdtnjUqVnvh29rR37PQFzPbLXqhyOyX0=
 sigs.k8s.io/kustomize v2.0.3+incompatible/go.mod h1:MkjgH3RdOWrievjo6c9T245dYlB5QeXV4WCbnt/PEpU=
-sigs.k8s.io/kustomize/kyaml v0.10.19 h1:us4+KUSKRpSox16AmjHkYORIlkWuQSLUaU5iGL7kkK4=
-sigs.k8s.io/kustomize/kyaml v0.10.19/go.mod h1:h94DSoDbmnN4BTc6VTX7tGNGXZy29rbPo+R4jGMvA8U=
+sigs.k8s.io/kustomize/kyaml v0.10.21 h1:KdoEgz3HzmcaLUTFqs6aaqFpsaA9MVRIwOZbi8vMaD0=
+sigs.k8s.io/kustomize/kyaml v0.10.21/go.mod h1:TYWhGwW9vjoRh3rWqBwB/ZOXyEGRVWe7Ggc3+KZIO+c=
 sigs.k8s.io/structured-merge-diff v0.0.0-20190525122527-15d366b2352e/go.mod h1:wWxsB5ozmmv/SG7nM11ayaAW51xMvak/t1r0CSlcokI=
 sigs.k8s.io/structured-merge-diff v1.0.1-0.20191108220359-b1b620dd3f06 h1:zD2IemQ4LmOcAumeiyDWXKUI2SO0NYDe3H6QGvPOVgU=
 sigs.k8s.io/structured-merge-diff v1.0.1-0.20191108220359-b1b620dd3f06/go.mod h1:/ULNhyfzRopfcjskuui0cTITekDduZ7ycKN3oUT9R18=
diff --git a/pkg/update/testdata/leave/expected/cronjob.yaml b/pkg/update/testdata/leave/expected/cronjob.yaml
index d6d6acf2..2b2d05e1 100644
--- a/pkg/update/testdata/leave/expected/cronjob.yaml
+++ b/pkg/update/testdata/leave/expected/cronjob.yaml
@@ -10,5 +10,5 @@ spec:
       template:
         spec:
           containers:
-          - name: c
-            image: helloworld:v1.0.0
+            - name: c
+              image: helloworld:v1.0.0
diff --git a/pkg/update/testdata/leave/expected/deployment.yaml b/pkg/update/testdata/leave/expected/deployment.yaml
index 54705513..94da5378 100644
--- a/pkg/update/testdata/leave/expected/deployment.yaml
+++ b/pkg/update/testdata/leave/expected/deployment.yaml
@@ -7,5 +7,8 @@ spec:
   template:
     spec:
       containers:
-      - name: c
-        image: helloworld:v1.0.0
+        - name: c
+          image: helloworld:v1.0.0
+          args:
+            # prove that go-yaml/yaml v3.0.0-20200615113413-eeeca48fe776 fixes https://github.com/kubernetes-sigs/kustomize/issues/3969
+            - mv /etc/resolv.conf /etc/resolv.conf.OLD && ln -s /run/systemd/resolve/resolv.conf /etc/resolv.conf
diff --git a/pkg/update/testdata/leave/original/deployment.yaml b/pkg/update/testdata/leave/original/deployment.yaml
index 54705513..1c1d1cbc 100644
--- a/pkg/update/testdata/leave/original/deployment.yaml
+++ b/pkg/update/testdata/leave/original/deployment.yaml
@@ -9,3 +9,6 @@ spec:
       containers:
       - name: c
         image: helloworld:v1.0.0
+        args:
+          # prove that go-yaml/yaml v3.0.0-20200615113413-eeeca48fe776 fixes https://github.com/kubernetes-sigs/kustomize/issues/3969
+          - mv /etc/resolv.conf /etc/resolv.conf.OLD && ln -s /run/systemd/resolve/resolv.conf /etc/resolv.conf
diff --git a/pkg/update/testdata/replace/commented-expected/deployment.yaml b/pkg/update/testdata/replace/commented-expected/deployment.yaml
index d0f0fcdd..9bd9ef46 100644
--- a/pkg/update/testdata/replace/commented-expected/deployment.yaml
+++ b/pkg/update/testdata/replace/commented-expected/deployment.yaml
@@ -5,7 +5,9 @@ metadata:
   namespace: bar
 spec:
   template:
-    spec:
+    # prove that go-yaml/yaml v3.0.0-20200615113413-eeeca48fe776 fixes https://github.com/kubernetes-sigs/kustomize/issues/3605
+    # 컨테이너
+    spec: # 컨테이너
       containers:
-      - name: c
-        image: used:v1.1.0 # the comment must stay!
+        - name: c
+          image: used:v1.1.0 # the comment must stay!
diff --git a/pkg/update/testdata/replace/commented/deployment.yaml b/pkg/update/testdata/replace/commented/deployment.yaml
index 6e503f6a..a9489146 100644
--- a/pkg/update/testdata/replace/commented/deployment.yaml
+++ b/pkg/update/testdata/replace/commented/deployment.yaml
@@ -5,7 +5,9 @@ metadata:
   namespace: bar
 spec:
   template:
-    spec:
+    # prove that go-yaml/yaml v3.0.0-20200615113413-eeeca48fe776 fixes https://github.com/kubernetes-sigs/kustomize/issues/3605
+    # 컨테이너
+    spec: # 컨테이너
       containers:
       - name: c
         image: used:v1.0.0 # the comment must stay!
diff --git a/pkg/update/testdata/replace/expected/cronjob.yaml b/pkg/update/testdata/replace/expected/cronjob.yaml
index 1c2adac9..24a4d2db 100644
--- a/pkg/update/testdata/replace/expected/cronjob.yaml
+++ b/pkg/update/testdata/replace/expected/cronjob.yaml
@@ -10,5 +10,5 @@ spec:
       template:
         spec:
           containers:
-          - name: c
-            image: used:v1.1.0
+            - name: c
+              image: used:v1.1.0
diff --git a/pkg/update/testdata/replace/expected/deployment.yaml b/pkg/update/testdata/replace/expected/deployment.yaml
index 308b7a03..8bd02bd1 100644
--- a/pkg/update/testdata/replace/expected/deployment.yaml
+++ b/pkg/update/testdata/replace/expected/deployment.yaml
@@ -7,5 +7,5 @@ spec:
   template:
     spec:
       containers:
-      - name: c
-        image: used:v1.1.0
+        - name: c
+          image: used:v1.1.0
diff --git a/pkg/update/testdata/setters/expected/kustomization.yaml b/pkg/update/testdata/setters/expected/kustomization.yaml
index 39c4fad5..a096ae86 100644
--- a/pkg/update/testdata/setters/expected/kustomization.yaml
+++ b/pkg/update/testdata/setters/expected/kustomization.yaml
@@ -2,8 +2,8 @@
 apiVersion: kustomize.config.k8s.io/v1beta1
 kind: Kustomization
 resources:
-- unimportant.yaml
+  - unimportant.yaml
 images:
-- name: container
-  newName: index.repo.fake/updated # {"$imagepolicy": "automation-ns:policy:name"}
-  newTag: v1.0.1 # {"$imagepolicy": "automation-ns:policy:tag"}
+  - name: container
+    newName: index.repo.fake/updated # {"$imagepolicy": "automation-ns:policy:name"}
+    newTag: v1.0.1 # {"$imagepolicy": "automation-ns:policy:tag"}
diff --git a/pkg/update/testdata/setters/expected/marked.yaml b/pkg/update/testdata/setters/expected/marked.yaml
index 1875968a..19254d92 100644
--- a/pkg/update/testdata/setters/expected/marked.yaml
+++ b/pkg/update/testdata/setters/expected/marked.yaml
@@ -10,7 +10,7 @@ spec:
       template:
         spec:
           containers:
-          - name: c
-            image: index.repo.fake/updated:v1.0.1 # {"$imagepolicy": "automation-ns:policy"}
-          - name: d
-            image: image:v1.0.0 # {"$imagepolicy": "automation-ns:unchanged"}
+            - name: c
+              image: index.repo.fake/updated:v1.0.1 # {"$imagepolicy": "automation-ns:policy"}
+            - name: d
+              image: image:v1.0.0 # {"$imagepolicy": "automation-ns:unchanged"}