diff --git a/build.gradle b/build.gradle
index 335826fa8..ba14f516f 100644
--- a/build.gradle
+++ b/build.gradle
@@ -3,7 +3,7 @@ allprojects {
     sourceCompatibility = 1.7
     targetCompatibility = 1.7
 
-    version 'v0.12.0'
+    version 'v0.13.0'
 
     repositories {
         jcenter()
diff --git a/extractor/src/main/java/org/schabi/newpipe/extractor/InfoItemsCollector.java b/extractor/src/main/java/org/schabi/newpipe/extractor/InfoItemsCollector.java
index c9ee7401c..2a3cb5f3a 100644
--- a/extractor/src/main/java/org/schabi/newpipe/extractor/InfoItemsCollector.java
+++ b/extractor/src/main/java/org/schabi/newpipe/extractor/InfoItemsCollector.java
@@ -27,7 +27,7 @@ import java.util.List;
  * along with NewPipe.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-public abstract class InfoItemsCollector<I extends InfoItem, E> implements Collector<I,E> {
+public abstract class InfoItemsCollector<I extends InfoItem, E extends InfoItemExtractor> implements Collector<I,E> {
 
     private final List<I> itemList = new ArrayList<>();
     private final List<Throwable> errors = new ArrayList<>();