diff --git a/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java b/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java
index d65fb0b24..fe82c07f6 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java
@@ -294,12 +294,6 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
             Thread thread = new Thread(runnable);
             thread.setName("Smack Cached Executor");
             thread.setDaemon(true);
-            thread.setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
-                @Override
-                public void uncaughtException(Thread t, Throwable e) {
-                    LOGGER.log(Level.WARNING, t + " encountered uncaught exception", e);
-                }
-            });
             return thread;
         }
     });
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java b/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java
index d14a82d46..7115a2bc3 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java
@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2003-2007 Jive Software, 2017-2019 Florian Schmaus.
+ * Copyright 2003-2007 Jive Software, 2017-2018 Florian Schmaus.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,8 +25,6 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.Set;
-import java.util.logging.Level;
-import java.util.logging.Logger;
 
 import javax.net.SocketFactory;
 import javax.net.ssl.HostnameVerifier;
@@ -48,7 +46,6 @@ import org.jxmpp.jid.impl.JidCreate;
 import org.jxmpp.jid.parts.Resourcepart;
 import org.jxmpp.stringprep.XmppStringprepException;
 import org.minidns.dnsname.DnsName;
-import org.minidns.dnsname.InvalidDnsNameException;
 import org.minidns.util.InetAddressUtil;
 
 /**
@@ -64,8 +61,6 @@ public abstract class ConnectionConfiguration {
         SmackConfiguration.getVersion();
     }
 
-    private static final Logger LOGGER = Logger.getLogger(ConnectionConfiguration.class.getName());
-
     /**
      * The XMPP domain of the XMPP Service. Usually servers use the same service name as the name
      * of the server. However, there are some servers like google where host would be
@@ -73,8 +68,6 @@ public abstract class ConnectionConfiguration {
      */
     protected final DomainBareJid xmppServiceDomain;
 
-    protected final DnsName xmppServiceDomainDnsName;
-
     protected final InetAddress hostAddress;
     protected final DnsName host;
     protected final int port;
@@ -147,19 +140,6 @@ public abstract class ConnectionConfiguration {
         if (xmppServiceDomain == null) {
             throw new IllegalArgumentException("Must define the XMPP domain");
         }
-
-        DnsName xmppServiceDomainDnsName;
-        try {
-            xmppServiceDomainDnsName = DnsName.from(xmppServiceDomain);
-        } catch (InvalidDnsNameException e) {
-            LOGGER.log(Level.INFO,
-                            "Could not transform XMPP service domain '" + xmppServiceDomain
-                          + "' to a DNS name. TLS X.509 certificate validiation may not be possible.",
-                            e);
-            xmppServiceDomainDnsName = null;
-        }
-        this.xmppServiceDomainDnsName = xmppServiceDomainDnsName;
-
         hostAddress = builder.hostAddress;
         host = builder.host;
         port = builder.port;
@@ -221,17 +201,6 @@ public abstract class ConnectionConfiguration {
         return xmppServiceDomain;
     }
 
-    /**
-     * Returns the XMPP service domain as DNS name if possible. Note that since not every XMPP address domainpart is a
-     * valid DNS name, this method may return <code>null</code>.
-     *
-     * @return the XMPP service domain as DNS name or <code>null</code>.
-     * @since 4.3.4
-     */
-    public DnsName getXmppServiceDomainAsDnsNameIfPossible() {
-        return xmppServiceDomainDnsName;
-    }
-
     /**
      * Returns the TLS security mode used when making the connection. By default,
      * the mode is {@link SecurityMode#ifpossible}.
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/xhtmlim/XHTMLText.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/xhtmlim/XHTMLText.java
index 2ef66949f..b08507ad0 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/xhtmlim/XHTMLText.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/xhtmlim/XHTMLText.java
@@ -105,7 +105,7 @@ public class XHTMLText {
     private XHTMLText appendOpenBodyTag(String style, String lang) {
         text.halfOpenElement(Message.BODY);
         text.xmlnsAttribute(NAMESPACE);
-        text.optAttribute(STYLE, style);
+        text.optElement(STYLE, style);
         text.xmllangAttribute(lang);
         text.rightAngleBracket();
         return this;
diff --git a/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java b/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java
index 0329ef4b1..a08221ddb 100644
--- a/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java
+++ b/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java
@@ -141,7 +141,6 @@ import org.jxmpp.jid.impl.JidCreate;
 import org.jxmpp.jid.parts.Resourcepart;
 import org.jxmpp.stringprep.XmppStringprepException;
 import org.jxmpp.util.XmppStringUtils;
-import org.minidns.dnsname.DnsName;
 import org.xmlpull.v1.XmlPullParser;
 import org.xmlpull.v1.XmlPullParserException;
 
@@ -862,27 +861,8 @@ public class XMPPTCPConnection extends AbstractXMPPConnection {
         final HostnameVerifier verifier = getConfiguration().getHostnameVerifier();
         if (verifier == null) {
                 throw new IllegalStateException("No HostnameVerifier set. Use connectionConfiguration.setHostnameVerifier() to configure.");
-        }
-
-        final String verifierHostname;
-        {
-            DnsName xmppServiceDomainDnsName = getConfiguration().getXmppServiceDomainAsDnsNameIfPossible();
-            // Try to convert the XMPP service domain, which potentially includes Unicode characters, into ASCII
-            // Compatible Encoding (ACE) to match RFC3280 dNSname IA5String constraint.
-            // See also: https://bugzilla.mozilla.org/show_bug.cgi?id=280839#c1
-            if (xmppServiceDomainDnsName != null) {
-                verifierHostname = xmppServiceDomainDnsName.ace;
-            }
-            else {
-                LOGGER.log(Level.WARNING, "XMPP service domain name '" + getXMPPServiceDomain()
-                                + "' can not be represented as DNS name. TLS X.509 certificate validiation may fail.");
-                verifierHostname = getXMPPServiceDomain().toString();
-            }
-        }
-        if (!verifier.verify(verifierHostname, sslSocket.getSession())) {
-            throw new CertificateException(
-                            "Hostname verification of certificate failed. Certificate does not authenticate "
-                                            + getXMPPServiceDomain());
+        } else if (!verifier.verify(getXMPPServiceDomain().toString(), sslSocket.getSession())) {
+            throw new CertificateException("Hostname verification of certificate failed. Certificate does not authenticate " + getXMPPServiceDomain());
         }
 
         // Set that TLS was successful