diff --git a/arduino-core/src/cc/arduino/contributions/libraries/LibrariesIndexer.java b/arduino-core/src/cc/arduino/contributions/libraries/LibrariesIndexer.java
index a09eb2a46..5adcbf201 100644
--- a/arduino-core/src/cc/arduino/contributions/libraries/LibrariesIndexer.java
+++ b/arduino-core/src/cc/arduino/contributions/libraries/LibrariesIndexer.java
@@ -106,6 +106,10 @@ public class LibrariesIndexer {
     rescanLibraries();
   }
 
+  public List<File> getLibrariesFolders() {
+    return librariesFolders;
+  }
+
   public void rescanLibraries() {
     // Clear all installed flags
     installedLibraries.clear();
diff --git a/arduino-core/src/processing/app/BaseNoGui.java b/arduino-core/src/processing/app/BaseNoGui.java
index 62cfd0d68..e08207b0e 100644
--- a/arduino-core/src/processing/app/BaseNoGui.java
+++ b/arduino-core/src/processing/app/BaseNoGui.java
@@ -679,8 +679,9 @@ public class BaseNoGui {
     // Libraries located in the latest folders on the list can override
     // other libraries with the same name.
     librariesIndexer.setSketchbookLibrariesFolder(getSketchbookLibrariesFolder());
-    librariesIndexer.setLibrariesFolders(librariesFolders);
-    librariesIndexer.rescanLibraries();
+    if (librariesIndexer.getLibrariesFolders() == null || !librariesIndexer.getLibrariesFolders().equals(librariesFolders)) {
+      librariesIndexer.setLibrariesFolders(librariesFolders);
+    }
 
     populateImportToLibraryTable();
   }