diff --git a/smack-core/src/main/java/org/jivesoftware/smack/util/StringUtils.java b/smack-core/src/main/java/org/jivesoftware/smack/util/StringUtils.java
index 77bc402c3..5ebe4c116 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/util/StringUtils.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/util/StringUtils.java
@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2003-2007 Jive Software, 2016-2020 Florian Schmaus.
+ * Copyright 2003-2007 Jive Software, 2016-2021 Florian Schmaus.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,6 +20,7 @@ package org.jivesoftware.smack.util;
 import java.io.IOException;
 import java.nio.CharBuffer;
 import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Iterator;
@@ -605,4 +606,13 @@ public class StringUtils {
         String[] lines = input.split(PORTABLE_NEWLINE_REGEX);
         return Arrays.asList(lines);
     }
+
+    public static List<String> toStrings(Collection<? extends CharSequence> charSequences) {
+        List<String> res = new ArrayList<>(charSequences.size());
+        for (CharSequence cs : charSequences) {
+            String string = cs.toString();
+            res.add(string);
+        }
+        return res;
+    }
 }
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/caps/EntityCapsManager.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/caps/EntityCapsManager.java
index 034d0f9dd..7f481ab21 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/caps/EntityCapsManager.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/caps/EntityCapsManager.java
@@ -700,7 +700,7 @@ public final class EntityCapsManager extends Manager {
             for (FormField f : fs) {
                 sb.append(f.getFieldName());
                 sb.append('<');
-                formFieldValuesToCaps(f.getRawValues(), sb);
+                formFieldValuesToCaps(f.getRawValueCharSequences(), sb);
             }
         }
 
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/FormNode.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/FormNode.java
index 3a6945f0f..ef8f3373c 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/FormNode.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/FormNode.java
@@ -38,11 +38,7 @@ public class FormNode extends NodeExtension {
      * @param submitForm The form
      */
     public FormNode(FormNodeType formType, DataForm submitForm) {
-        super(formType.getNodeElement());
-
-        if (submitForm == null)
-            throw new IllegalArgumentException("Submit form cannot be null");
-        configForm = submitForm;
+        this(formType, null, submitForm);
     }
 
     /**
@@ -55,9 +51,6 @@ public class FormNode extends NodeExtension {
      */
     public FormNode(FormNodeType formType, String nodeId, DataForm submitForm) {
         super(formType.getNodeElement(), nodeId);
-
-        if (submitForm == null)
-            throw new IllegalArgumentException("Submit form cannot be null");
         configForm = submitForm;
     }
 
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/provider/FormNodeProvider.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/provider/FormNodeProvider.java
index e7d8b0946..5c5d71dc7 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/provider/FormNodeProvider.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/provider/FormNodeProvider.java
@@ -35,6 +35,11 @@ import org.jivesoftware.smackx.xdata.packet.DataForm;
 public class FormNodeProvider extends EmbeddedExtensionProvider<FormNode> {
     @Override
     protected FormNode createReturnExtension(String currentElement, String currentNamespace, Map<String, String> attributeMap, List<? extends XmlElement> content) {
-        return new FormNode(FormNodeType.valueOfFromElementName(currentElement, currentNamespace), attributeMap.get("node"), (DataForm) content.iterator().next());
+        DataForm dataForm = null;
+        if (!content.isEmpty()) {
+            dataForm = (DataForm) content.get(0);
+        }
+
+        return new FormNode(FormNodeType.valueOfFromElementName(currentElement, currentNamespace), attributeMap.get("node"), dataForm);
     }
 }
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/AbstractMultiFormField.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/AbstractMultiFormField.java
index 4b1c092b3..16ccc3c7f 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/AbstractMultiFormField.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/AbstractMultiFormField.java
@@ -27,35 +27,26 @@ import org.jxmpp.util.XmppDateTime;
 
 public class AbstractMultiFormField extends FormField {
 
-    private final List<String> values;
-
-    private final List<String> rawValues;
+    private final List<Value> values;
 
     protected AbstractMultiFormField(Builder<?, ?> builder) {
         super(builder);
         values = CollectionUtil.cloneAndSeal(builder.values);
-        rawValues = CollectionUtil.cloneAndSeal(builder.rawValues);
     }
 
     @Override
-    public final List<String> getValues() {
+    public final List<Value> getRawValues() {
         return values;
     }
 
-    @Override
-    public final List<String> getRawValues() {
-        return rawValues;
-    }
-
     public abstract static class Builder<F extends AbstractMultiFormField, B extends FormField.Builder<F, B>>
                     extends FormField.Builder<F, B> {
 
-        private List<String> values;
-        private List<String> rawValues;
+        private List<Value> values;
 
         protected Builder(AbstractMultiFormField formField) {
             super(formField);
-            values = CollectionUtil.newListWith(formField.getValues());
+            values = CollectionUtil.newListWith(formField.getRawValues());
         }
 
         protected Builder(String fieldName, FormField.Type type) {
@@ -65,7 +56,6 @@ public class AbstractMultiFormField extends FormField {
         private void ensureValuesAreInitialized() {
             if (values == null) {
                 values = new ArrayList<>();
-                rawValues = new ArrayList<>();
             }
         }
 
@@ -77,11 +67,13 @@ public class AbstractMultiFormField extends FormField {
         public abstract B addValue(CharSequence value);
 
         public B addValueVerbatim(CharSequence value) {
+            return addValueVerbatim(new Value(value));
+        }
+
+        public B addValueVerbatim(Value value) {
             ensureValuesAreInitialized();
 
-            String valueString = value.toString();
-            values.add(valueString);
-            rawValues.add(valueString);
+            values.add(value);
             return getThis();
         }
 
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/AbstractSingleStringValueFormField.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/AbstractSingleStringValueFormField.java
index 4530d3968..9e57a294e 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/AbstractSingleStringValueFormField.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/AbstractSingleStringValueFormField.java
@@ -74,8 +74,15 @@ public class AbstractSingleStringValueFormField extends SingleValueFormField {
             return setValue(value);
         }
 
+        public B setValue(Value value) {
+            this.value = value.getValue().toString();
+            this.rawValue = value;
+            return getThis();
+        }
+
         public B setValue(CharSequence value) {
-            this.rawValue = this.value = value.toString();
+            this.value = value.toString();
+            rawValue = new Value(this.value);
             return getThis();
         }
 
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/BooleanFormField.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/BooleanFormField.java
index e87278ae9..85e351649 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/BooleanFormField.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/BooleanFormField.java
@@ -71,17 +71,21 @@ public class BooleanFormField extends SingleValueFormField {
         @Deprecated
         // TODO: Remove in Smack 4.6.
         public Builder addValue(CharSequence value) {
-            return setValue(value);
+            return setValue(new Value(value));
         }
 
         public Builder setValue(CharSequence value) {
-            rawValue = value.toString();
-            boolean valueBoolean = ParserUtils.parseXmlBoolean(rawValue);
-            return setValue(valueBoolean);
+            return setValue(new Value(value));
+        }
+
+        public Builder setValue(Value value) {
+            this.value = ParserUtils.parseXmlBoolean(value.getValue().toString());
+            rawValue = value;
+            return getThis();
         }
 
         public Builder setValue(boolean value) {
-            rawValue = Boolean.toString(value);
+            rawValue = new Value(Boolean.toString(value));
             this.value = value;
             return this;
         }
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/FormField.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/FormField.java
index 8f4e9aafd..acf4f276d 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/FormField.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/FormField.java
@@ -269,9 +269,25 @@ public abstract class FormField implements XmlElement {
      *
      * @return a List of the default values or answered values of the question.
      */
-    public abstract List<? extends CharSequence> getValues();
+    public List<? extends CharSequence> getValues() {
+        return getRawValueCharSequences();
+    }
 
-    public abstract List<String> getRawValues();
+    public abstract List<Value> getRawValues();
+
+    private transient List<CharSequence> rawValueCharSequences;
+
+    public final List<CharSequence> getRawValueCharSequences() {
+        if (rawValueCharSequences == null) {
+            List<Value> rawValues = getRawValues();
+            rawValueCharSequences = new ArrayList<>(rawValues.size());
+            for (Value value : rawValues) {
+                rawValueCharSequences.add(value.value);
+            }
+        }
+
+        return rawValueCharSequences;
+    }
 
     public boolean hasValueSet() {
         List<?> values = getValues();
@@ -385,12 +401,15 @@ public abstract class FormField implements XmlElement {
 
     protected transient List<XmlElement> extraXmlChildElements;
 
+    /**
+     * Populate @{link {@link #extraXmlChildElements}}. Note that this method may be overridden by subclasses.
+     */
     protected void populateExtraXmlChildElements() {
-        List<? extends CharSequence> values = getValues();
+        List<Value> values = getRawValues();
+        // Note that we need to create a new ArrayList here, since subclasses may add to it by overriding
+        // populateExtraXmlChildElements.
         extraXmlChildElements = new ArrayList<>(values.size());
-        for (CharSequence value : values) {
-            extraXmlChildElements.add(new Value(value));
-        }
+        extraXmlChildElements.addAll(values);
     }
 
     @Override
@@ -414,7 +433,8 @@ public abstract class FormField implements XmlElement {
             populateExtraXmlChildElements();
         }
 
-        if (formFieldChildElements.isEmpty() && extraXmlChildElements == null) {
+        if (formFieldChildElements.isEmpty()
+                        && (extraXmlChildElements == null || extraXmlChildElements.isEmpty())) {
             buf.closeEmptyElement();
         } else {
             buf.rightAngleBracket();
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/JidMultiFormField.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/JidMultiFormField.java
index a5c869c18..39d8357af 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/JidMultiFormField.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/JidMultiFormField.java
@@ -23,13 +23,14 @@ import java.util.List;
 import org.jivesoftware.smack.util.CollectionUtil;
 
 import org.jxmpp.jid.Jid;
-import org.jxmpp.jid.util.JidUtil;
+import org.jxmpp.jid.impl.JidCreate;
+import org.jxmpp.stringprep.XmppStringprepException;
 
 public final class JidMultiFormField extends FormField {
 
     private final List<Jid> values;
 
-    private final List<String> rawValues;
+    private final List<Value> rawValues;
 
     JidMultiFormField(Builder builder) {
         super(builder);
@@ -43,7 +44,7 @@ public final class JidMultiFormField extends FormField {
     }
 
     @Override
-    public List<String> getRawValues() {
+    public List<Value> getRawValues() {
         return rawValues;
     }
 
@@ -54,7 +55,7 @@ public final class JidMultiFormField extends FormField {
     public static final class Builder extends FormField.Builder<JidMultiFormField, JidMultiFormField.Builder> {
         private List<Jid> values;
 
-        private List<String> rawValues;
+        private List<Value> rawValues;
 
         private Builder(JidMultiFormField jidMultiFormField) {
             super(jidMultiFormField);
@@ -79,27 +80,29 @@ public final class JidMultiFormField extends FormField {
         }
 
         public Builder addValue(Jid jid) {
-            return addValue(jid, null);
-        }
-
-        public Builder addValue(Jid jid, String rawValue) {
-            if (rawValue == null) {
-                rawValue = jid.toString();
-            }
+            Value value = new Value(jid);
 
             ensureValuesAreInitialized();
-
             values.add(jid);
-            rawValues.add(rawValue);
+            rawValues.add(value);
+
+            return getThis();
+        }
+
+        public Builder addValue(Value value) throws XmppStringprepException {
+            Jid jid = JidCreate.from(value.getValue());
+
+            ensureValuesAreInitialized();
+            values.add(jid);
+            rawValues.add(value);
 
             return this;
         }
 
         public Builder addValues(Collection<? extends Jid> jids) {
-            ensureValuesAreInitialized();
-
-            values.addAll(jids);
-            rawValues.addAll(JidUtil.toStringList(jids));
+            for (Jid jid : jids) {
+                addValue(jid);
+            }
             return this;
         }
 
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/JidSingleFormField.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/JidSingleFormField.java
index 7948971a3..ec5ec4c70 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/JidSingleFormField.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/JidSingleFormField.java
@@ -17,6 +17,8 @@
 package org.jivesoftware.smackx.xdata;
 
 import org.jxmpp.jid.Jid;
+import org.jxmpp.jid.impl.JidCreate;
+import org.jxmpp.stringprep.XmppStringprepException;
 
 public class JidSingleFormField extends SingleValueFormField {
 
@@ -60,11 +62,13 @@ public class JidSingleFormField extends SingleValueFormField {
 
         public Builder setValue(Jid value, String rawValue) {
             this.value = value;
-            if (rawValue != null) {
-                this.rawValue = rawValue;
-            } else {
-                this.rawValue = value.toString();
-            }
+            this.rawValue = new Value(value);
+            return getThis();
+        }
+
+        public Builder setValue(Value value) throws XmppStringprepException {
+            this.value = JidCreate.from(value.getValue());
+            this.rawValue = value;
             return this;
         }
 
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/SingleValueFormField.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/SingleValueFormField.java
index 796abd654..d4b389a96 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/SingleValueFormField.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/SingleValueFormField.java
@@ -23,7 +23,7 @@ import org.jivesoftware.smack.util.CollectionUtil;
 
 public abstract class SingleValueFormField extends FormField {
 
-    private final String rawValue;
+    private final Value rawValue;
 
     protected SingleValueFormField(Builder<?, ?> builder) {
         super(builder);
@@ -38,24 +38,23 @@ public abstract class SingleValueFormField extends FormField {
 
     public abstract CharSequence getValue();
 
-    public final String getRawValue() {
+    public final Value getRawValue() {
         return rawValue;
     }
 
     @Override
-    public final List<String> getRawValues() {
-        String rawValue = getRawValue();
+    public final List<Value> getRawValues() {
+        Value rawValue = getRawValue();
         return CollectionUtil.emptyOrSingletonListFrom(rawValue);
     }
 
     @Override
     protected void populateExtraXmlChildElements() {
-        CharSequence value = getValue();
-        if (value == null) {
+        if (rawValue == null) {
             return;
         }
 
-        extraXmlChildElements = Collections.singletonList(new Value(value));
+        extraXmlChildElements = Collections.singletonList(rawValue);
     }
 
     public abstract static class Builder<F extends SingleValueFormField, B extends Builder<F, B>>
@@ -65,11 +64,12 @@ public abstract class SingleValueFormField extends FormField {
             super(fieldName, type);
         }
 
-        protected Builder(FormField formField) {
+        protected Builder(SingleValueFormField formField) {
             super(formField);
+            rawValue = formField.getRawValue();
         }
 
-        protected String rawValue;
+        protected Value rawValue;
 
         @Override
         protected void resetInternal() {
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/form/FormReader.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/form/FormReader.java
index 493abd25a..043e9a1fe 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/form/FormReader.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/form/FormReader.java
@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2020 Florian Schmaus
+ * Copyright 2020-2021 Florian Schmaus
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,6 +21,8 @@ import java.util.Collections;
 import java.util.Date;
 import java.util.List;
 
+import org.jivesoftware.smack.util.StringUtils;
+
 import org.jivesoftware.smackx.xdata.AbstractMultiFormField;
 import org.jivesoftware.smackx.xdata.AbstractSingleStringValueFormField;
 import org.jivesoftware.smackx.xdata.BooleanFormField;
@@ -54,7 +56,8 @@ public interface FormReader {
             return Collections.emptyList();
         }
         AbstractMultiFormField multiFormField = formField.ifPossibleAs(AbstractMultiFormField.class);
-        return multiFormField.getValues();
+        List<? extends CharSequence> charSequences =  multiFormField.getValues();
+        return StringUtils.toStrings(charSequences);
     }
 
     default Boolean readBoolean(String fieldName) {
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/provider/DataFormProvider.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/provider/DataFormProvider.java
index f6362660c..0be42d61f 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/provider/DataFormProvider.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xdata/provider/DataFormProvider.java
@@ -49,9 +49,6 @@ import org.jivesoftware.smackx.xdata.packet.DataForm;
 import org.jivesoftware.smackx.xdatalayout.packet.DataLayout;
 import org.jivesoftware.smackx.xdatalayout.provider.DataLayoutProvider;
 
-import org.jxmpp.jid.Jid;
-import org.jxmpp.jid.impl.JidCreate;
-
 /**
  * The DataFormProvider parses DataForm packets.
  *
@@ -237,9 +234,7 @@ public class DataFormProvider extends ExtensionElementProvider<DataForm> {
         case jid_multi:
             JidMultiFormField.Builder jidMultiBuilder = FormField.jidMultiBuilder(fieldName);
             for (FormField.Value value : values) {
-                String rawValue = value.getValue().toString();
-                Jid jid = JidCreate.from(rawValue);
-                jidMultiBuilder.addValue(jid, rawValue);
+                jidMultiBuilder.addValue(value);
             }
             builder = jidMultiBuilder;
             break;
@@ -247,9 +242,8 @@ public class DataFormProvider extends ExtensionElementProvider<DataForm> {
             ensureAtMostSingleValue(type, values);
             JidSingleFormField.Builder jidSingleBuilder = FormField.jidSingleBuilder(fieldName);
             if (!values.isEmpty()) {
-                String rawValue = values.get(0).getValue().toString();
-                Jid jid = JidCreate.from(rawValue);
-                jidSingleBuilder.setValue(jid, rawValue);
+                FormField.Value value = values.get(0);
+                jidSingleBuilder.setValue(value);
             }
             builder = jidSingleBuilder;
             break;
@@ -303,7 +297,7 @@ public class DataFormProvider extends ExtensionElementProvider<DataForm> {
         BooleanFormField.Builder builder = FormField.booleanBuilder(fieldName);
         ensureAtMostSingleValue(builder.getType(), values);
         if (values.size() == 1) {
-            String value = values.get(0).getValue().toString();
+            FormField.Value value = values.get(0);
             builder.setValue(value);
         }
         return builder;