diff --git a/app/src/processing/app/Base.java b/app/src/processing/app/Base.java
index d346de61d..a7141d7da 100644
--- a/app/src/processing/app/Base.java
+++ b/app/src/processing/app/Base.java
@@ -27,6 +27,7 @@ import java.awt.event.*;
 import java.io.*;
 import java.util.*;
 import java.util.List;
+import java.util.concurrent.ConcurrentHashMap;
 
 import javax.jmdns.ServiceEvent;
 import javax.swing.*;
@@ -116,7 +117,7 @@ public class Base {
 //  int editorCount;
   List<Editor> editors = Collections.synchronizedList(new ArrayList<Editor>());
   Editor activeEditor;
-  final Map<String, Map<String, Object>> boardsViaNetwork;
+  private final Map<String, Map<String, Object>> boardsViaNetwork;
 
   static File portableFolder = null;
   static final String portableSketchbookFolder = "sketchbook";
@@ -257,7 +258,7 @@ public class Base {
   public Base(String[] args) throws Exception {
     platform.init(this);
 
-    this.boardsViaNetwork = new HashMap<String, Map<String, Object>>();
+    this.boardsViaNetwork = new ConcurrentHashMap<String, Map<String, Object>>();
 
     // Get the sketchbook path, and make sure it's set properly
     String sketchbookPath = Preferences.get("sketchbook.path");
@@ -423,6 +424,9 @@ public class Base {
     });
   }
 
+  public Map<String, Map<String, Object>> getBoardsViaNetwork() {
+    return new HashMap<String, Map<String, Object>>(boardsViaNetwork);
+  }
 
   /**
    * Post-constructor setup for the editor area. Loads the last
diff --git a/app/src/processing/app/Editor.java b/app/src/processing/app/Editor.java
index 0cc25863c..4709d99fb 100644
--- a/app/src/processing/app/Editor.java
+++ b/app/src/processing/app/Editor.java
@@ -1004,7 +1004,7 @@ public class Editor extends JFrame implements RunnerListener {
       exception.printStackTrace();
     }
 
-    for (Map.Entry<String, Map<String, Object>> entry : base.boardsViaNetwork.entrySet()) {
+    for (Map.Entry<String, Map<String, Object>> entry : base.getBoardsViaNetwork().entrySet()) {
       Inet4Address[] a = (Inet4Address[]) entry.getValue().get("addresses");
       String label = entry.getKey() + "@" + a[0].toString();
       JCheckBoxMenuItem rbMenuItem = new JCheckBoxMenuItem(label, label.equals(Preferences.get("serial.port")));
diff --git a/app/src/processing/app/zeroconf/Discovery.java b/app/src/processing/app/zeroconf/Discovery.java
index ba95163d1..bda225e08 100644
--- a/app/src/processing/app/zeroconf/Discovery.java
+++ b/app/src/processing/app/zeroconf/Discovery.java
@@ -2,10 +2,7 @@ package processing.app.zeroconf;
 
 import processing.app.zeroconf.jmdns.ArduinoDNSTaskStarter;
 
-import javax.jmdns.JmDNS;
-import javax.jmdns.NetworkTopologyDiscovery;
-import javax.jmdns.ServiceEvent;
-import javax.jmdns.ServiceListener;
+import javax.jmdns.*;
 import javax.jmdns.impl.DNSTaskStarter;
 import java.io.IOException;
 import java.net.InetAddress;
diff --git a/app/src/processing/app/zeroconf/jmdns/ArduinoDNSTaskStarter.java b/app/src/processing/app/zeroconf/jmdns/ArduinoDNSTaskStarter.java
index 3243ae48d..fe9c25715 100644
--- a/app/src/processing/app/zeroconf/jmdns/ArduinoDNSTaskStarter.java
+++ b/app/src/processing/app/zeroconf/jmdns/ArduinoDNSTaskStarter.java
@@ -18,6 +18,7 @@ public class ArduinoDNSTaskStarter implements DNSTaskStarter.Factory.ClassDelega
 
       public void purgeTimer() {
         delegate.purgeTimer();
+        timer.purge();
       }
 
       public void purgeStateTimer() {