diff --git a/internal/featuredetection/feature_detection.go b/internal/featuredetection/feature_detection.go
index e40c134bc..7a200e20c 100644
--- a/internal/featuredetection/feature_detection.go
+++ b/internal/featuredetection/feature_detection.go
@@ -23,15 +23,13 @@ type Detector interface {
 }
 
 type IssueFeatures struct {
-	StateReason          bool
-	StateReasonDuplicate bool
-	ActorIsAssignable    bool
+	StateReason       bool
+	ActorIsAssignable bool
 }
 
 var allIssueFeatures = IssueFeatures{
-	StateReason:          true,
-	StateReasonDuplicate: true,
-	ActorIsAssignable:    true,
+	StateReason:       true,
+	ActorIsAssignable: true,
 }
 
 type PullRequestFeatures struct {
@@ -140,9 +138,8 @@ func (d *detector) IssueFeatures() (IssueFeatures, error) {
 	}
 
 	features := IssueFeatures{
-		StateReason:          false,
-		StateReasonDuplicate: false,
-		ActorIsAssignable:    false, // replaceActorsForAssignable GraphQL mutation unavailable on GHES
+		StateReason:       false,
+		ActorIsAssignable: false, // replaceActorsForAssignable GraphQL mutation unavailable on GHES
 	}
 
 	var featureDetection struct {
@@ -151,11 +148,6 @@ func (d *detector) IssueFeatures() (IssueFeatures, error) {
 				Name string
 			} `graphql:"fields(includeDeprecated: true)"`
 		} `graphql:"Issue: __type(name: \"Issue\")"`
-		IssueClosedStateReason struct {
-			EnumValues []struct {
-				Name string
-			} `graphql:"enumValues(includeDeprecated: true)"`
-		} `graphql:"IssueClosedStateReason: __type(name: \"IssueClosedStateReason\")"`
 	}
 
 	gql := api.NewClientFromHTTP(d.httpClient)
@@ -170,15 +162,6 @@ func (d *detector) IssueFeatures() (IssueFeatures, error) {
 		}
 	}
 
-	if features.StateReason {
-		for _, enumValue := range featureDetection.IssueClosedStateReason.EnumValues {
-			if enumValue.Name == "DUPLICATE" {
-				features.StateReasonDuplicate = true
-				break
-			}
-		}
-	}
-
 	return features, nil
 }
 
diff --git a/internal/featuredetection/feature_detection_test.go b/internal/featuredetection/feature_detection_test.go
index 7417cc7d8..032f5cda0 100644
--- a/internal/featuredetection/feature_detection_test.go
+++ b/internal/featuredetection/feature_detection_test.go
@@ -23,9 +23,8 @@ func TestIssueFeatures(t *testing.T) {
 			name:     "github.com",
 			hostname: "github.com",
 			wantFeatures: IssueFeatures{
-				StateReason:          true,
-				StateReasonDuplicate: true,
-				ActorIsAssignable:    true,
+				StateReason:       true,
+				ActorIsAssignable: true,
 			},
 			wantErr: false,
 		},
@@ -33,9 +32,8 @@ func TestIssueFeatures(t *testing.T) {
 			name:     "ghec data residency (ghe.com)",
 			hostname: "stampname.ghe.com",
 			wantFeatures: IssueFeatures{
-				StateReason:          true,
-				StateReasonDuplicate: true,
-				ActorIsAssignable:    true,
+				StateReason:       true,
+				ActorIsAssignable: true,
 			},
 			wantErr: false,
 		},
@@ -46,50 +44,23 @@ func TestIssueFeatures(t *testing.T) {
 				`query Issue_fields\b`: `{"data": {}}`,
 			},
 			wantFeatures: IssueFeatures{
-				StateReason:          false,
-				StateReasonDuplicate: false,
-				ActorIsAssignable:    false,
+				StateReason:       false,
+				ActorIsAssignable: false,
 			},
 			wantErr: false,
 		},
 		{
-			name:     "GHE has state reason field without duplicate enum",
+			name:     "GHE has state reason field",
 			hostname: "git.my.org",
 			queryResponse: map[string]string{
 				`query Issue_fields\b`: heredoc.Doc(`
 					{ "data": { "Issue": { "fields": [
 						{"name": "stateReason"}
-					] }, "IssueClosedStateReason": { "enumValues": [
-						{"name": "COMPLETED"},
-						{"name": "NOT_PLANNED"}
 					] } } }
 				`),
 			},
 			wantFeatures: IssueFeatures{
-				StateReason:          true,
-				StateReasonDuplicate: false,
-				ActorIsAssignable:    false,
-			},
-			wantErr: false,
-		},
-		{
-			name:     "GHE has duplicate state reason enum value",
-			hostname: "git.my.org",
-			queryResponse: map[string]string{
-				`query Issue_fields\b`: heredoc.Doc(`
-					{ "data": { "Issue": { "fields": [
-						{"name": "stateReason"}
-					] }, "IssueClosedStateReason": { "enumValues": [
-						{"name": "COMPLETED"},
-						{"name": "NOT_PLANNED"},
-						{"name": "DUPLICATE"}
-					] } } }
-				`),
-			},
-			wantFeatures: IssueFeatures{
-				StateReason:          true,
-				StateReasonDuplicate: true,
-				ActorIsAssignable:    false,
+				StateReason: true,
 			},
 			wantErr: false,
 		},
diff --git a/pkg/cmd/issue/close/close.go b/pkg/cmd/issue/close/close.go
index 4c1c7d382..ab7e30688 100644
--- a/pkg/cmd/issue/close/close.go
+++ b/pkg/cmd/issue/close/close.go
@@ -196,12 +196,6 @@ func apiClose(httpClient *http.Client, repo ghrepo.Interface, issue *api.Issue,
 				return fmt.Errorf("closing as duplicate is not supported on %s", repo.RepoHost())
 			}
 			reason = ""
-		} else if reason == "duplicate" && !features.StateReasonDuplicate {
-			if duplicateIssueID != "" {
-				return fmt.Errorf("closing as duplicate is not supported on %s", repo.RepoHost())
-			}
-			// If DUPLICATE is not supported silently close issue without setting StateReason.
-			reason = ""
 		}
 	}
 
diff --git a/pkg/cmd/issue/close/close_test.go b/pkg/cmd/issue/close/close_test.go
index ddab71210..300fe5fc5 100644
--- a/pkg/cmd/issue/close/close_test.go
+++ b/pkg/cmd/issue/close/close_test.go
@@ -16,15 +16,6 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-type issueFeaturesDetectorMock struct {
-	fd.EnabledDetectorMock
-	issueFeatures fd.IssueFeatures
-}
-
-func (md *issueFeaturesDetectorMock) IssueFeatures() (fd.IssueFeatures, error) {
-	return md.issueFeatures, nil
-}
-
 func TestNewCmdClose(t *testing.T) {
 	// Test shared parsing of issue number / URL.
 	argparsetest.TestArgParsing(t, NewCmdClose)
@@ -282,71 +273,6 @@ func TestCloseRun(t *testing.T) {
 			},
 			wantStderr: "✓ Closed issue OWNER/REPO#13 (The title of the issue)\n",
 		},
-		{
-			name: "close issue with duplicate reason when duplicate is not supported",
-			opts: &CloseOptions{
-				IssueNumber: 13,
-				Reason:      "duplicate",
-				Detector: &issueFeaturesDetectorMock{
-					issueFeatures: fd.IssueFeatures{
-						StateReason:          true,
-						StateReasonDuplicate: false,
-					},
-				},
-			},
-			httpStubs: func(reg *httpmock.Registry) {
-				reg.Register(
-					httpmock.GraphQL(`query IssueByNumber\b`),
-					httpmock.StringResponse(`
-            { "data": { "repository": {
-              "hasIssuesEnabled": true,
-              "issue": { "id": "THE-ID", "number": 13, "title": "The title of the issue"}
-            } } }`),
-				)
-				reg.Register(
-					httpmock.GraphQL(`mutation IssueClose\b`),
-					httpmock.GraphQLMutation(`{"id": "THE-ID"}`,
-						func(inputs map[string]interface{}) {
-							assert.Equal(t, 1, len(inputs))
-							assert.Equal(t, "THE-ID", inputs["issueId"])
-						}),
-				)
-			},
-			wantStderr: "✓ Closed issue OWNER/REPO#13 (The title of the issue)\n",
-		},
-		{
-			name: "close issue as duplicate when duplicate is not supported",
-			opts: &CloseOptions{
-				IssueNumber: 13,
-				DuplicateOf: "99",
-				Detector: &issueFeaturesDetectorMock{
-					issueFeatures: fd.IssueFeatures{
-						StateReason:          true,
-						StateReasonDuplicate: false,
-					},
-				},
-			},
-			httpStubs: func(reg *httpmock.Registry) {
-				reg.Register(
-					httpmock.GraphQL(`query IssueByNumber\b`),
-					httpmock.StringResponse(`
-            { "data": { "repository": {
-              "hasIssuesEnabled": true,
-              "issue": { "id": "THE-ID", "number": 13, "title": "The title of the issue"}
-            } } }`),
-				)
-				reg.Register(
-					httpmock.GraphQL(`query IssueByNumber\b`),
-					httpmock.StringResponse(`
-            { "data": { "repository": {
-              "hasIssuesEnabled": true,
-              "issue": { "id": "DUPLICATE-ID", "number": 99}
-            } } }`),
-				)
-			},
-			wantErr: true,
-			errMsg:  "closing as duplicate is not supported on github.com",
-		},
 		{
 			name: "duplicate of cannot point to same issue",
 			opts: &CloseOptions{