added comments

src/main/java/org/jabref/gui/util/uithreadaware/UiThreadObservableList.java

@@ -9,6 +9,11 @@
 import javafx.collections.ListChangeListener;
 import javafx.collections.ObservableList;
 
+/**
+ * This class can be used to wrap an @see ObservableList inside it. When wrapped, any Listener listening for updates to the wrapped ObservableList (for example because of a binding to it) is ensured to be notified on the JavaFX Application Thread. It should be used to implement bindings where updates come in from a background thread but should be reflected in the UI where it is necessary that changes to the UI are performed on the JavaFX Application thread.
+ *
+ * @param <E> the type of the elements of the wrapped ObservableList.
+ */
 public class UiThreadObservableList<E> implements ObservableList<E> {
 
     private final ObservableList<E> delegate;

src/main/java/org/jabref/gui/util/uithreadaware/UiThreadStringProperty.java

@@ -5,6 +5,10 @@
 import javafx.beans.value.ChangeListener;
 import javafx.beans.value.ObservableValue;
 
+/**
+ * This class can be used to wrap a @see StringProperty inside it. When wrapped, any Listener listening for updates to the wrapped StringProperty (for example because of a binding to it) is ensured to be notified on the JavaFX Application Thread. It should be used to implement bindings where updates come in from a background thread but should be reflected in the UI where it is necessary that changes to the UI are performed on the JavaFX Application thread.
+ *
+ */
 public class UiThreadStringProperty extends StringProperty {
 
     private final StringProperty delegate;
@@ -45,7 +49,7 @@ public String get() {
 
     @Override
     public void set(String value) {
-        UiThreadHelper.ensureUiThreadExecution(() -> delegate.set(value));
+        delegate.set(value);
     }
 
     @Override