diff --git a/src/model/event.cpp b/src/model/event.cpp
index e331bb1..b83784e 100644
--- a/src/model/event.cpp
+++ b/src/model/event.cpp
@@ -1,158 +1,160 @@
 /*
  * Copyright (c) 2019 Alexander Potashev <aspotashev@gmail.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation; either version 2 of
  * the License or (at your option) version 3 or any later version
  * accepted by the membership of KDE e.V. (or its successor approved
  * by the membership of KDE e.V.), which shall act as a proxy
  * defined in Section 14 of version 3 of the license.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include "event.h"
 
 #include <KLocalizedString>
 
 #include "ktt_debug.h"
 #include "ktimetrackerutility.h"
 
 static const QByteArray eventAppName = QByteArray("ktimetracker");
 
 Event::Event(const KCalendarCore::Event::Ptr &event)
     : m_summary(event->summary())
     , m_dtStart(event->dtStart())
     , m_dtEnd(event->hasEndDate() ? event->dtEnd() : QDateTime())
     , m_uid(event->uid())
     , m_relatedTo(event->relatedTo())
     , m_comments(event->comments())
     , m_duration(0)
 {
     if (!m_dtStart.isValid()) {
         qFatal("1");
     }
 
     bool ok = false;
     m_duration = getCustomProperty(event, QStringLiteral("duration")).toInt(&ok);
     if (!ok) {
         m_duration = 0;
     }
 }
 
 QString Event::summary() const
 {
     return m_summary;
 }
 
 void Event::updateDuration(QDateTime &changedDt, const QDateTime &otherDt)
 {
     if (m_duration < 0) {
         // Was a negative duration task
         if (m_dtEnd > m_dtStart) {
             // If range is not trivial or inversed, we assume that
             // event duration now becomes positive, thus we should update it here.
             m_duration = m_dtStart.secsTo(m_dtEnd);
         }
     } else {
         // Was a regular task, and will stay regular. Calculate duration if possible.
         if (hasEndDate()) {
             m_duration = m_dtStart.secsTo(m_dtEnd);
             if (m_duration < 0) {
                 // We cannot make duration negative.
                 // May be the user tried to make duration zero, let us help him.
                 m_duration = 0;
                 changedDt = otherDt;
             }
         }
     }
 }
 
 void Event::setDtStart(const QDateTime &dtStart)
 {
     m_dtStart = dtStart;
     updateDuration(m_dtStart, m_dtEnd);
 }
 
 QDateTime Event::dtStart() const
 {
     return m_dtStart;
 }
 
 void Event::setDtEnd(const QDateTime &dtEnd)
 {
     m_dtEnd = dtEnd;
     updateDuration(m_dtEnd, m_dtStart);
 }
 
 bool Event::hasEndDate() const
 {
     return m_dtEnd.isValid();
 }
 
 QDateTime Event::dtEnd() const
 {
     return m_dtEnd;
 }
 
 QString Event::uid() const
 {
     return m_uid;
 }
 
 QString Event::relatedTo() const
 {
     return m_relatedTo;
 }
 
 void Event::addComment(const QString &comment)
 {
-    m_comments.append(comment);
+    if (m_comments.isEmpty() || comment != m_comments.last()) {
+        m_comments.append(comment);
+    }
 }
 
 QStringList Event::comments() const
 {
     return m_comments;
 }
 
 void Event::setDuration(long seconds)
 {
     m_duration = seconds;
 }
 
 long Event::duration() const
 {
     return m_duration;
 }
 
 KCalendarCore::Event::Ptr Event::asCalendarEvent(const KCalendarCore::Event::Ptr &event) const
 {
     Q_ASSERT(event != nullptr);
 
     qCDebug(KTT_LOG) << "Task::asTodo: uid" << m_uid << ", summary" << m_summary;
 
     event->setSummary(summary());
     event->setDtStart(m_dtStart);
     if (hasEndDate()) {
         event->setDtEnd(m_dtEnd);
     }
     event->setUid(uid());
     event->setRelatedTo(relatedTo());
     for (const auto &comment : comments()) {
         event->addComment(comment);
     }
 
     // Use a custom property to keep a record of negative durations
     event->setCustomProperty(eventAppName, QByteArray("duration"), QString::number(m_duration));
 
     event->setCategories({i18n("KTimeTracker")});
 
     return event;
 }