diff --git a/app/src/processing/app/Mode.java b/app/src/processing/app/Mode.java
index 6dc13581f..704ae8f3c 100644
--- a/app/src/processing/app/Mode.java
+++ b/app/src/processing/app/Mode.java
@@ -661,7 +661,6 @@ public abstract class Mode {
     DefaultMutableTreeNode root = new DefaultMutableTreeNode("Examples");
 
     try {
-
       File[] examples = getExampleCategoryFolders();
 
       for (File subFolder : examples) {
@@ -706,7 +705,7 @@ public abstract class Mode {
 
     DefaultMutableTreeNode contributedExamplesNode =
       buildContributedExamplesTrees();
-    if(contributedExamplesNode.getChildCount() > 0){
+    if (contributedExamplesNode.getChildCount() > 0) {
       root.add(contributedExamplesNode);
     }
 
@@ -721,27 +720,28 @@ public abstract class Mode {
     try {
       File[] subfolders =
         ContributionType.EXAMPLES.listCandidates(examplesContribFolder);
-      if (subfolders == null) {
-        subfolders = new File[0]; //empty array
-      }
-      for (File sub : subfolders) {
-        if (!ExamplesContribution.isCompatible(base, sub))
-          continue;
-        DefaultMutableTreeNode subNode =
-          new DefaultMutableTreeNode(sub.getName());
-        if (base.addSketches(subNode, sub)) {
-          contribExamplesNode.add(subNode);
-          int exampleNodeNumber = -1;
-          for (int y = 0; y < subNode.getChildCount(); y++)
-            if (subNode.getChildAt(y).toString().equals("examples"))
-              exampleNodeNumber = y;
-          if (exampleNodeNumber == -1)
-            continue;
-          TreeNode exampleNode = subNode.getChildAt(exampleNodeNumber);
-          subNode.remove(exampleNodeNumber);
-          int count = exampleNode.getChildCount();
-          for (int x = 0; x < count; x++) {
-            subNode.add((DefaultMutableTreeNode) exampleNode.getChildAt(0));
+      if (subfolders != null) {
+        for (File sub : subfolders) {
+          if (ExamplesContribution.isCompatible(base, sub)) {
+            DefaultMutableTreeNode subNode =
+              new DefaultMutableTreeNode(sub.getName());
+            if (base.addSketches(subNode, sub)) {
+              contribExamplesNode.add(subNode);
+              int exampleNodeNumber = -1;
+              for (int y = 0; y < subNode.getChildCount(); y++) {
+                if (subNode.getChildAt(y).toString().equals("examples")) {
+                  exampleNodeNumber = y;
+                }
+              }
+              if (exampleNodeNumber != -1) {
+                TreeNode exampleNode = subNode.getChildAt(exampleNodeNumber);
+                subNode.remove(exampleNodeNumber);
+                int count = exampleNode.getChildCount();
+                for (int x = 0; x < count; x++) {
+                  subNode.add((DefaultMutableTreeNode) exampleNode.getChildAt(0));
+                }
+              }
+            }
           }
         }
       }
diff --git a/app/src/processing/app/contrib/AvailableContribution.java b/app/src/processing/app/contrib/AvailableContribution.java
index 6e000393b..e4efed583 100644
--- a/app/src/processing/app/contrib/AvailableContribution.java
+++ b/app/src/processing/app/contrib/AvailableContribution.java
@@ -239,8 +239,9 @@ public class AvailableContribution extends Contribution {
       StringDict properties = Util.readSettings(propFile);
 
       String name = properties.get("name");
-      if (name == null || name.isEmpty())
+      if (name == null || name.isEmpty()) {
         name = getName();
+      }
 
       String category;
       StringList categoryList = parseCategories(properties);
@@ -248,15 +249,6 @@ public class AvailableContribution extends Contribution {
           categoryList.get(0).equals(UNKNOWN_CATEGORY)) {
         category = getCategoryStr();
       } else {
-        /*
-        StringBuilder sb = new StringBuilder();
-        for (String cat : categories) {
-          sb.append(cat);
-          sb.append(',');
-        }
-        sb.deleteCharAt(sb.length() - 1);
-        category = sb.toString();
-        */
         category = categoryList.join(",");
       }
 
@@ -299,7 +291,6 @@ public class AvailableContribution extends Contribution {
         prettyVersion = getPrettyVersion();
 
       String compatibleContribsList = null;
-
       if (getType() == ContributionType.EXAMPLES) {
         compatibleContribsList = properties.get(MODES_PROPERTY);
       }
@@ -352,7 +343,9 @@ public class AvailableContribution extends Contribution {
           writer.println("imports=" + importsList.join(","));
         }
         if (getType() == ContributionType.EXAMPLES) {
-          writer.println(MODES_PROPERTY + "=" + compatibleContribsList);
+          if (compatibleContribsList != null) {
+            writer.println(MODES_PROPERTY + "=" + compatibleContribsList);
+          }
         }
 
         writer.flush();
diff --git a/app/src/processing/app/contrib/Contribution.java b/app/src/processing/app/contrib/Contribution.java
index c67b5b14f..f99b3cbcf 100644
--- a/app/src/processing/app/contrib/Contribution.java
+++ b/app/src/processing/app/contrib/Contribution.java
@@ -31,11 +31,8 @@ import processing.app.Language;
 
 abstract public class Contribution {
   static final String IMPORTS_PROPERTY = "imports";
-//  static final String CATEGORIES_PROPERTY = "category";
   static final String CATEGORIES_PROPERTY = "categories";
-  //static final String MODES_PROPERTY = "compatibleModesList";
   static final String MODES_PROPERTY = "modes";
-  //static final String AUTHORS_PROPERTY = "authorList";
   static final String AUTHORS_PROPERTY = "authors";
 
   static final String SPECIAL_CATEGORY = "Starred";
diff --git a/app/src/processing/app/contrib/ExamplesContribution.java b/app/src/processing/app/contrib/ExamplesContribution.java
index 7dfb2dbb2..fb547646b 100644
--- a/app/src/processing/app/contrib/ExamplesContribution.java
+++ b/app/src/processing/app/contrib/ExamplesContribution.java
@@ -33,6 +33,13 @@ public class ExamplesContribution extends LocalContribution {
 
   static private StringList parseModeList(StringDict properties) {
     String unparsedModes = properties.get(MODES_PROPERTY);
+
+    // Workaround for 3.0 alpha/beta bug for 3.0b2
+    if ("null".equals(unparsedModes)) {
+      properties.remove(MODES_PROPERTY);
+      unparsedModes = null;
+    }
+
     StringList outgoing = new StringList();
     if (unparsedModes != null) {
       outgoing.append(PApplet.trim(PApplet.split(unparsedModes, ',')));
@@ -51,14 +58,15 @@ public class ExamplesContribution extends LocalContribution {
    *         active editor
    */
   static public boolean isCompatible(Base base, File exampleFolder) {
-    String currentIdentifier = base.getActiveEditor().getMode().getIdentifier();
+    String currentIdentifier =
+      base.getActiveEditor().getMode().getIdentifier();
     File propertiesFile =
       new File(exampleFolder, EXAMPLES.getPropertiesName());
     if (propertiesFile.exists()) {
       StringList compatibleList =
         parseModeList(Util.readSettings(propertiesFile));
       if (compatibleList.size() == 0) {
-        return true;  // if no mode specified, just include everywhere
+        return true;  // if no mode specified, assume compatible everywhere
       }
       for (String c : compatibleList) {
         if (c.equals(currentIdentifier)) {
diff --git a/todo.txt b/todo.txt
index 8f0d61e2e..d06385f3c 100644
--- a/todo.txt
+++ b/todo.txt
@@ -12,6 +12,8 @@ X Initialize the Find dialog with the current selection
 X   https://github.com/processing/processing/issues/3457
 X Links in error bar are not selectable nor clickable
 X   https://github.com/processing/processing/issues/3471
+X Show contributed examples in the Examples window
+X   https://github.com/processing/processing/issues/3420
 
 export
 X save export settings to preferences