diff --git a/jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/JSON.java b/jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/JSON.java
index 3e3bf115..49f84c90 100644
--- a/jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/JSON.java
+++ b/jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/JSON.java
@@ -1685,6 +1685,11 @@ private static class ExtContextImpl extends ExtensionContext {
             _builder = b;
         }
 
+        @Override
+        public boolean isEnabled(JSON.Feature feature) {
+            return _builder.isEnabled(feature);
+        }
+        
         @Override
         public ExtensionContext setTreeCodec(TreeCodec tc) {
             _builder.treeCodec(tc);
diff --git a/jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/api/ExtensionContext.java b/jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/api/ExtensionContext.java
index 743c7108..d43a1cc2 100644
--- a/jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/api/ExtensionContext.java
+++ b/jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/api/ExtensionContext.java
@@ -1,6 +1,7 @@
 package com.fasterxml.jackson.jr.ob.api;
 
 import com.fasterxml.jackson.core.TreeCodec;
+import com.fasterxml.jackson.jr.ob.JSON;
 
 /**
  * API that lets {@link com.fasterxml.jackson.jr.ob.JacksonJrExtension}s to register handlers
@@ -10,6 +11,19 @@
  */
 public abstract class ExtensionContext
 {
+    // // // Config access
+
+    /**
+     * Method for checking whether given {@code JSON.Feature} is enabled.
+     *
+     * @param feature Feature to check
+     *
+     * @return True if given {@code JSON.Feature} is enabled; {@code false} if not
+     *
+     * @since 2.17
+     */
+    public abstract boolean isEnabled(JSON.Feature feature);
+    
     // // // Override of (and access to) singleton handlers
 
     /**
diff --git a/jr-stree/src/main/java/com/fasterxml/jackson/jr/stree/JacksonJrsTreeCodec.java b/jr-stree/src/main/java/com/fasterxml/jackson/jr/stree/JacksonJrsTreeCodec.java
index ac77559b..48a7a9db 100644
--- a/jr-stree/src/main/java/com/fasterxml/jackson/jr/stree/JacksonJrsTreeCodec.java
+++ b/jr-stree/src/main/java/com/fasterxml/jackson/jr/stree/JacksonJrsTreeCodec.java
@@ -16,8 +16,11 @@ public class JacksonJrsTreeCodec extends TreeCodec
 
     public static final JacksonJrsTreeCodec SINGLETON = new JacksonJrsTreeCodec();
 
-    protected ObjectCodec _objectCodec;
+    protected final ObjectCodec _objectCodec;
 
+    // @since 2.17
+    protected boolean _failOnDuplicateKeys;
+    
     public JacksonJrsTreeCodec() {
         this(null);
     }
@@ -26,6 +29,11 @@ public JacksonJrsTreeCodec(ObjectCodec codec) {
         _objectCodec = codec;
     }
 
+    // @since 2.17
+    public void setFailOnDuplicateKeys(boolean state) {
+        _failOnDuplicateKeys = state;
+    }
+    
     @SuppressWarnings("unchecked")
     @Override
     public <T extends TreeNode> T readTree(JsonParser p) throws IOException {
diff --git a/jr-stree/src/main/java/com/fasterxml/jackson/jr/stree/JrSimpleTreeExtension.java b/jr-stree/src/main/java/com/fasterxml/jackson/jr/stree/JrSimpleTreeExtension.java
index 9d8954f2..d3588fcc 100644
--- a/jr-stree/src/main/java/com/fasterxml/jackson/jr/stree/JrSimpleTreeExtension.java
+++ b/jr-stree/src/main/java/com/fasterxml/jackson/jr/stree/JrSimpleTreeExtension.java
@@ -1,5 +1,6 @@
 package com.fasterxml.jackson.jr.stree;
 
+import com.fasterxml.jackson.jr.ob.JSON;
 import com.fasterxml.jackson.jr.ob.JacksonJrExtension;
 import com.fasterxml.jackson.jr.ob.api.ExtensionContext;
 
@@ -23,9 +24,10 @@ public JrSimpleTreeExtension() {
     public JrSimpleTreeExtension(JacksonJrsTreeCodec tc) {
         _codec = tc;
     }
-    
+
     @Override
     protected void register(ExtensionContext ctxt) {
+        _codec.setFailOnDuplicateKeys(ctxt.isEnabled(JSON.Feature.FAIL_ON_DUPLICATE_MAP_KEYS));
         ctxt.setTreeCodec(_codec);
     }
 }
diff --git a/release-notes/VERSION-2.x b/release-notes/VERSION-2.x
index 6d33f36e..e39aa513 100644
--- a/release-notes/VERSION-2.x
+++ b/release-notes/VERSION-2.x
@@ -15,6 +15,7 @@ Not yet released
 
 #7: Support deserialization of `int[]`
  (contributed by @Shounaks) 
+#131: Add mechanism for `JacksonJrExtension`s to access state of `JSON.Feature`s
 
 2.17.0-rc1 (26-Feb-2024)