diff --git a/arduino-core/src/cc/arduino/contributions/libraries/LibrariesIndexer.java b/arduino-core/src/cc/arduino/contributions/libraries/LibrariesIndexer.java
index deaaeec90..86cfcbd1f 100644
--- a/arduino-core/src/cc/arduino/contributions/libraries/LibrariesIndexer.java
+++ b/arduino-core/src/cc/arduino/contributions/libraries/LibrariesIndexer.java
@@ -74,7 +74,7 @@ public class LibrariesIndexer {
     mapper.registerModule(new MrBeanModule());
     mapper.configure(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY, true);
     mapper.configure(DeserializationFeature.EAGER_DESERIALIZER_FETCH, true);
-    mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, true);
+    mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
     index = mapper.readValue(indexIn, LibrariesIndex.class);
 
     for (ContributedLibrary library : index.getLibraries()) {
diff --git a/arduino-core/src/cc/arduino/contributions/packages/ContributionsIndexer.java b/arduino-core/src/cc/arduino/contributions/packages/ContributionsIndexer.java
index ce96187a6..a5a069c0f 100644
--- a/arduino-core/src/cc/arduino/contributions/packages/ContributionsIndexer.java
+++ b/arduino-core/src/cc/arduino/contributions/packages/ContributionsIndexer.java
@@ -98,7 +98,7 @@ public class ContributionsIndexer {
     mapper.registerModule(new MrBeanModule());
     mapper.configure(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY, true);
     mapper.configure(DeserializationFeature.EAGER_DESERIALIZER_FETCH, true);
-    mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, true);
+    mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
     index = mapper.readValue(indexIn, ContributionsIndex.class);
   }