diff --git a/.ci/build.sh b/.ci/build.sh
index a5cee646..84716662 100644
--- a/.ci/build.sh
+++ b/.ci/build.sh
@@ -3,7 +3,7 @@ set -ex
 source shared-ci/prepare-archlinux.sh
 
 # See *depends in https://github.com/archlinuxcn/repo/blob/master/archlinuxcn/qtermwidget-git/PKGBUILD
-pacman -S --noconfirm --needed git cmake lxqt-build-tools-git qt5-tools python-pyqt5 pyqt-builder sip
+pacman -S --noconfirm --needed git cmake lxqt-build-tools-git qt6-5compat qt6-tools python-pyqt6 pyqt-builder sip
 
 cmake -B build -S . \
     -DBUILD_EXAMPLE=ON \
@@ -11,4 +11,4 @@ cmake -B build -S . \
 make -C build
 
 cd pyqt
-CXXFLAGS="-I$PWD/../lib -I$PWD/../build/lib" LDFLAGS="-L$PWD/../build" sip-wheel --verbose
+CXXFLAGS="-I$PWD/../lib -I$PWD/../build/lib" LDFLAGS="-L$PWD/../build" sip-wheel --verbose --qmake=/usr/bin/qmake6
diff --git a/CMakeLists.txt b/CMakeLists.txt
index ce50ed02..d6dbbc05 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,8 +21,8 @@ option(USE_UTF8PROC "Use libutf8proc for better Unicode support. Default OFF" OF
 
 # just change version for releases
 # keep this in sync with the version in pyqt/pyproject.toml
-set(QTERMWIDGET_VERSION_MAJOR "1")
-set(QTERMWIDGET_VERSION_MINOR "4")
+set(QTERMWIDGET_VERSION_MAJOR "2")
+set(QTERMWIDGET_VERSION_MINOR "0")
 set(QTERMWIDGET_VERSION_PATCH "0")
 
 set(QTERMWIDGET_VERSION "${QTERMWIDGET_VERSION_MAJOR}.${QTERMWIDGET_VERSION_MINOR}.${QTERMWIDGET_VERSION_PATCH}")
@@ -32,12 +32,12 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${PROJECT_SOURCE_DIR}/cmake")
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 
 # Minimum Versions
-set(QT_MINIMUM_VERSION "5.15.0")
+set(QT_MINIMUM_VERSION "6.1.0")
 set(LXQTBT_MINIMUM_VERSION "0.13.0")
 
-find_package(Qt5Widgets "${QT_MINIMUM_VERSION}" REQUIRED)
-find_package(Qt5LinguistTools "${QT_MINIMUM_VERSION}" REQUIRED)
-find_package(lxqt-build-tools ${LXQTBT_MINIMUM_VERSION} REQUIRED)
+find_package(Qt6Widgets "${QT_MINIMUM_VERSION}" REQUIRED)
+find_package(Qt6LinguistTools "${QT_MINIMUM_VERSION}" REQUIRED)
+find_package(lxqt2-build-tools ${LXQTBT_MINIMUM_VERSION} REQUIRED)
 
 if(USE_UTF8PROC)
     find_package(Utf8Proc REQUIRED)
@@ -55,7 +55,7 @@ if(APPLE)
     endif()
 endif()
 
-set(QTERMWIDGET_LIBRARY_NAME qtermwidget5)
+set(QTERMWIDGET_LIBRARY_NAME qtermwidget6)
 
 
 # main library
@@ -130,9 +130,9 @@ set(QTERMWIDGET_INCLUDE_DIR "${CMAKE_INSTALL_FULL_INCLUDEDIR}/${QTERMWIDGET_LIBR
 
 CHECK_FUNCTION_EXISTS(updwtmpx HAVE_UPDWTMPX)
 
-qt5_wrap_cpp(MOCS ${HDRS})
-qt5_wrap_ui(UI_SRCS ${UI})
-set(PKG_CONFIG_REQ "Qt5Widgets")
+qt6_wrap_cpp(MOCS ${HDRS})
+qt6_wrap_ui(UI_SRCS ${UI})
+set(PKG_CONFIG_REQ "Qt6Widgets")
 
 lxqt_translate_ts(QTERMWIDGET_QM
     TRANSLATION_DIR "lib/translations"
@@ -147,7 +147,7 @@ lxqt_translate_ts(QTERMWIDGET_QM
 )
 
 add_library(${QTERMWIDGET_LIBRARY_NAME} SHARED ${SRCS} ${MOCS} ${UI_SRCS} ${QTERMWIDGET_QM})
-target_link_libraries(${QTERMWIDGET_LIBRARY_NAME} Qt5::Widgets)
+target_link_libraries(${QTERMWIDGET_LIBRARY_NAME} Qt6::Widgets)
 set_target_properties( ${QTERMWIDGET_LIBRARY_NAME} PROPERTIES
                        SOVERSION ${QTERMWIDGET_VERSION_MAJOR}
                        VERSION ${QTERMWIDGET_VERSION}
diff --git a/README.md b/README.md
index e77d2ab7..2e0e4d2b 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 ## Overview
 
-A terminal emulator widget for Qt 5.
+A terminal emulator widget for Qt 6.
 
 QTermWidget is an open-source project originally based on the KDE4 Konsole application, but it took its own direction later on.
 The main goal of this project is to provide a Unicode-enabled, embeddable Qt widget for using as a built-in console (or terminal emulation widget).
@@ -45,7 +45,7 @@ License: BSD-3-clause
 
 ### Compiling sources
 
-The only runtime dependency is qtbase ≥ 5.12.0.
+The only runtime dependency is qtbase ≥ 6.6.0.
 Build dependencies are as follows:
 - CMake ≥ 3.1.0 serves as the build system and therefore needs to be present to compile.
 - The latest [lxqt-build-tools](https://github.com/lxqt/lxqt-build-tools/) is also needed for compilation.
@@ -124,7 +124,6 @@ void | setSilenceTimeout(int _seconds_)
 void | setTerminalFont(QFont &_font_)
 void | setTerminalOpacity(qreal _level_)
 void | setTerminalSizeHint(bool _enabled_)
-void | setTextCodec(QTextCodec *_codec_)
 void | setWorkingDirectory(const QString &_dir_)
 void | startShellProgram()
 void | startTerminalTeletype()
@@ -325,9 +324,6 @@ Sets terminal font. Default is application font with family Monospace, size 10.
 __void setTerminalSizeHint(bool _enabled_)__\
 Exposes TerminalDisplay::TerminalSizeHint.
 
-__void setTextCodec(QTextCodec *_codec_)__\
-Sets text codec, default is UTF-8.
-
 <!--__void setWorkingDirectory(const QString &_dir_)__\-->
 <!--__void silence()__\-->
 
diff --git a/cmake/qtermwidget5-config.cmake.in b/cmake/qtermwidget6-config.cmake.in
similarity index 100%
rename from cmake/qtermwidget5-config.cmake.in
rename to cmake/qtermwidget6-config.cmake.in
diff --git a/examples/cpp/main.cpp b/examples/cpp/main.cpp
index 779d7bb5..ea085ccb 100644
--- a/examples/cpp/main.cpp
+++ b/examples/cpp/main.cpp
@@ -36,12 +36,12 @@ int main(int argc, char *argv[])
     QMenuBar *menuBar = new QMenuBar(mainWindow);
     QMenu *actionsMenu = new QMenu(QStringLiteral("Actions"), menuBar);
     menuBar->addMenu(actionsMenu);
-    actionsMenu->addAction(QStringLiteral("Find..."), console, &QTermWidget::toggleShowSearchBar,
-                           QKeySequence(Qt::CTRL + Qt::SHIFT + Qt::Key_F));
-    actionsMenu->addAction(QStringLiteral("Copy"), console, &QTermWidget::copyClipboard,
-                           QKeySequence(Qt::CTRL + Qt::SHIFT + Qt::Key_C));
-    actionsMenu->addAction(QStringLiteral("Paste"), console, &QTermWidget::pasteClipboard,
-                           QKeySequence(Qt::CTRL + Qt::SHIFT + Qt::Key_V));
+    actionsMenu->addAction(QStringLiteral("Find..."), QKeySequence(Qt::CTRL | Qt::SHIFT | Qt::Key_F), 
+        console, &QTermWidget::toggleShowSearchBar);
+    actionsMenu->addAction(QStringLiteral("Copy"), QKeySequence(Qt::CTRL | Qt::SHIFT | Qt::Key_C), 
+        console, &QTermWidget::copyClipboard);
+    actionsMenu->addAction(QStringLiteral("Paste"), QKeySequence(Qt::CTRL | Qt::SHIFT | Qt::Key_V), 
+        console, &QTermWidget::pasteClipboard);
     actionsMenu->addAction(QStringLiteral("About Qt"), &app, &QApplication::aboutQt);
     mainWindow->setMenuBar(menuBar);
 
diff --git a/lib/ColorScheme.cpp b/lib/ColorScheme.cpp
index 6af2058c..f749a83c 100644
--- a/lib/ColorScheme.cpp
+++ b/lib/ColorScheme.cpp
@@ -339,7 +339,7 @@ void ColorScheme::readColorEntry(QSettings * s , int index)
     bool ok = false;
     // XXX: Undocumented(?) QSettings behavior: values with commas are parsed
     // as QStringList and others QString
-    if (colorValue.type() == QVariant::StringList)
+    if (colorValue.typeId() == QVariant::StringList)
     {
         QStringList rgbList = colorValue.toStringList();
         colorStr = rgbList.join(QLatin1Char(','));
@@ -364,9 +364,9 @@ void ColorScheme::readColorEntry(QSettings * s , int index)
         if (hexColorPattern.match(colorStr).hasMatch())
         {
             // Parsing is always ok as already matched by the regexp
-            r = colorStr.midRef(1, 2).toInt(nullptr, 16);
-            g = colorStr.midRef(3, 2).toInt(nullptr, 16);
-            b = colorStr.midRef(5, 2).toInt(nullptr, 16);
+            r = colorStr.mid(1, 2).toInt(nullptr, 16);
+            g = colorStr.mid(3, 2).toInt(nullptr, 16);
+            b = colorStr.mid(5, 2).toInt(nullptr, 16);
             ok = true;
         }
     }
diff --git a/lib/Emulation.cpp b/lib/Emulation.cpp
index 08267d26..c88ac12a 100644
--- a/lib/Emulation.cpp
+++ b/lib/Emulation.cpp
@@ -33,7 +33,7 @@
 #include <QClipboard>
 #include <QHash>
 #include <QKeyEvent>
-#include <QRegExp>
+#include <QRegularExpression>
 #include <QTextStream>
 #include <QThread>
 
@@ -49,11 +49,10 @@ using namespace Konsole;
 
 Emulation::Emulation() :
   _currentScreen(nullptr),
-  _codec(nullptr),
-  _decoder(nullptr),
   _keyTranslator(nullptr),
   _usesMouse(false),
-  _bracketedPasteMode(false)
+  _bracketedPasteMode(false),
+  _fromUtf8(QStringEncoder::Utf16)
 {
   // create screens with a default size
   _screen[0] = new Screen(40,80);
@@ -126,7 +125,6 @@ Emulation::~Emulation()
 
   delete _screen[0];
   delete _screen[1];
-  delete _decoder;
 }
 
 void Emulation::setScreen(int n)
@@ -136,7 +134,7 @@ void Emulation::setScreen(int n)
   if (_currentScreen != old)
   {
      // tell all windows onto this emulation to switch to the newly active screen
-     for(ScreenWindow* window : qAsConst(_windows))
+     for(ScreenWindow* window : std::as_const(_windows))
          window->setScreen(_currentScreen);
   }
 }
@@ -157,27 +155,6 @@ const HistoryType& Emulation::history() const
   return _screen[0]->getScroll();
 }
 
-void Emulation::setCodec(const QTextCodec * qtc)
-{
-  if (qtc)
-      _codec = qtc;
-  else
-     setCodec(LocaleCodec);
-
-  delete _decoder;
-  _decoder = _codec->makeDecoder();
-
-  emit useUtf8Request(utf8());
-}
-
-void Emulation::setCodec(EmulationCodec codec)
-{
-    if ( codec == Utf8Codec )
-        setCodec( QTextCodec::codecForName("utf8") );
-    else if ( codec == LocaleCodec )
-        setCodec( QTextCodec::codecForLocale() );
-}
-
 void Emulation::setKeyBindings(const QString& name)
 {
   _keyTranslator = KeyboardTranslatorManager::instance()->findTranslator(name);
@@ -247,8 +224,9 @@ void Emulation::receiveData(const char* text, int length)
      * U+10FFFF
      * https://unicodebook.readthedocs.io/unicode_encodings.html#surrogates
      */
-    QString utf16Text = _decoder->toUnicode(text,length);
-    std::wstring unicodeText = utf16Text.toStdWString();
+    QString str = QString::fromUtf8(text, length);
+    auto encoded = _fromUtf8(str);
+    std::wstring unicodeText = encoded.data.toStdWString(); 
 
     //send characters to terminal emulator
     for (size_t i=0;i<unicodeText.length();i++)
diff --git a/lib/Emulation.h b/lib/Emulation.h
index 1217386e..98ba2fe1 100644
--- a/lib/Emulation.h
+++ b/lib/Emulation.h
@@ -29,9 +29,9 @@
 // Qt
 #include <QKeyEvent>
 //#include <QPointer>
-#include <QTextCodec>
 #include <QTextStream>
 #include <QTimer>
+#include <QStringEncoder>
 
 #include "qtermwidget_export.h"
 #include "KeyboardTranslator.h"
@@ -190,20 +190,6 @@ Q_OBJECT
    */
   virtual void writeToStream(TerminalCharacterDecoder* decoder,int startLine,int endLine);
 
-  /** Returns the codec used to decode incoming characters.  See setCodec() */
-  const QTextCodec* codec() const { return _codec; }
-  /** Sets the codec used to decode incoming characters.  */
-  void setCodec(const QTextCodec*);
-
-  /**
-   * Convenience method.
-   * Returns true if the current codec used to decode incoming
-   * characters is UTF-8
-   */
-  bool utf8() const
-  { Q_ASSERT(_codec); return _codec->mibEnum() == 106; }
-
-
   /** TODO Document me */
   virtual char eraseChar() const;
 
@@ -483,10 +469,6 @@ public slots:
                             //                      scrollbars are not enabled in this mode )
 
 
-  //decodes an incoming C-style character stream into a unicode QString using
-  //the current text codec.  (this allows for rendering of non-ASCII characters in text files etc.)
-  const QTextCodec* _codec;
-  QTextDecoder* _decoder;
   const KeyboardTranslator* _keyTranslator; // the keyboard layout
 
 protected slots:
@@ -512,7 +494,7 @@ private slots:
   bool _bracketedPasteMode;
   QTimer _bulkTimer1{this};
   QTimer _bulkTimer2{this};
-
+  QStringEncoder _fromUtf8;
 };
 
 }
diff --git a/lib/Filter.cpp b/lib/Filter.cpp
index f2192929..a4944260 100644
--- a/lib/Filter.cpp
+++ b/lib/Filter.cpp
@@ -338,11 +338,11 @@ QStringList RegExpFilter::HotSpot::capturedTexts() const
     return _capturedTexts;
 }
 
-void RegExpFilter::setRegExp(const QRegExp& regExp)
+void RegExpFilter::setRegExp(const QRegularExpression& regExp)
 {
     _searchText = regExp;
 }
-QRegExp RegExpFilter::regExp() const
+QRegularExpression RegExpFilter::regExp() const
 {
     return _searchText;
 }
@@ -352,7 +352,6 @@ QRegExp RegExpFilter::regExp() const
 }*/
 void RegExpFilter::process()
 {
-    int pos = 0;
     const QString* text = buffer();
 
     Q_ASSERT( text );
@@ -360,35 +359,41 @@ void RegExpFilter::process()
     // ignore any regular expressions which match an empty string.
     // otherwise the while loop below will run indefinitely
     static const QString emptyString;
-    if ( _searchText.exactMatch(emptyString) )
-        return;
-
-    while(pos >= 0)
+    auto match = _searchText.match(emptyString, 0, 
+        QRegularExpression::NormalMatch, QRegularExpression::AnchorAtOffsetMatchOption); 
+    if (match.hasMatch())
     {
-        pos = _searchText.indexIn(*text,pos);
-
-        if ( pos >= 0 )
-        {
-            int startLine = 0;
-            int endLine = 0;
-            int startColumn = 0;
-            int endColumn = 0;
+        return;
+    }
 
-            getLineColumn(pos,startLine,startColumn);
-            getLineColumn(pos + _searchText.matchedLength(),endLine,endColumn);
+    match = _searchText.match(*text);
+    while (match.hasMatch()) {
+        int startLine = 0;
+        int endLine = 0;
+        int startColumn = 0;
+        int endColumn = 0;
+
+        QStringList captureList;
+        for (int i = 0; i <= match.lastCapturedIndex(); i++) {
+            QString text = match.captured(i);
+            captureList.append(text);
+        }
+        
+        getLineColumn(match.capturedStart(), startLine, startColumn);
+        getLineColumn(match.capturedEnd(), endLine, endColumn);
 
-            RegExpFilter::HotSpot* spot = newHotSpot(startLine,startColumn,
-                                           endLine,endColumn);
-            spot->setCapturedTexts(_searchText.capturedTexts());
+        RegExpFilter::HotSpot* spot = newHotSpot(startLine, startColumn, endLine, endColumn);
+        spot->setCapturedTexts(captureList);
 
-            addHotSpot( spot );
-            pos += _searchText.matchedLength();
+        addHotSpot(spot);
 
-            // if matchedLength == 0, the program will get stuck in an infinite loop
-            if ( _searchText.matchedLength() == 0 )
-                pos = -1;
+        // if capturedLength == 0, the program will get stuck in an infinite loop
+        if (match.capturedLength() == 0) {
+            break;
         }
-    }
+
+        match = _searchText.match(*text, match.capturedEnd());
+    }	
 }
 
 RegExpFilter::HotSpot* RegExpFilter::newHotSpot(int startLine,int startColumn,
@@ -417,9 +422,9 @@ UrlFilter::HotSpot::UrlType UrlFilter::HotSpot::urlType() const
 {
     QString url = capturedTexts().constFirst();
 
-    if ( FullUrlRegExp.exactMatch(url) )
+    if ( FullUrlRegExp.match(url).hasMatch() )
         return StandardUrl;
-    else if ( EmailAddressRegExp.exactMatch(url) )
+    else if ( EmailAddressRegExp.match(url).hasMatch() )
         return Email;
     else
         return Unknown;
@@ -465,13 +470,13 @@ void UrlFilter::HotSpot::activate(const QString& actionName)
 //regexp matches:
 // full url:
 // protocolname:// or www. followed by anything other than whitespaces, <, >, ' or ", and ends before whitespaces, <, >, ', ", ], !, comma and dot
-const QRegExp UrlFilter::FullUrlRegExp(QLatin1String("(www\\.(?!\\.)|[a-z][a-z0-9+.-]*://)[^\\s<>'\"]+[^!,\\.\\s<>'\"\\]]"));
+const QRegularExpression UrlFilter::FullUrlRegExp(QLatin1String("(www\\.(?!\\.)|[a-z][a-z0-9+.-]*://)[^\\s<>'\"]+[^!,\\.\\s<>'\"\\]]"));
 // email address:
 // [word chars, dots or dashes]@[word chars, dots or dashes].[word chars]
-const QRegExp UrlFilter::EmailAddressRegExp(QLatin1String("\\b(\\w|\\.|-)+@(\\w|\\.|-)+\\.\\w+\\b"));
+const QRegularExpression UrlFilter::EmailAddressRegExp(QLatin1String("\\b(\\w|\\.|-)+@(\\w|\\.|-)+\\.\\w+\\b"));
 
 // matches full url or email address
-const QRegExp UrlFilter::CompleteUrlRegExp(QLatin1Char('(')+FullUrlRegExp.pattern()+QLatin1Char('|')+
+const QRegularExpression UrlFilter::CompleteUrlRegExp(QLatin1Char('(')+FullUrlRegExp.pattern()+QLatin1Char('|')+
                                             EmailAddressRegExp.pattern()+QLatin1Char(')'));
 
 UrlFilter::UrlFilter()
diff --git a/lib/Filter.h b/lib/Filter.h
index 3d8d4b7c..12847d10 100644
--- a/lib/Filter.h
+++ b/lib/Filter.h
@@ -26,7 +26,7 @@
 #include <QObject>
 #include <QStringList>
 #include <QHash>
-#include <QRegExp>
+#include <QRegularExpression>
 
 // Local
 #include "qtermwidget_export.h"
@@ -214,9 +214,9 @@ class QTERMWIDGET_EXPORT RegExpFilter : public Filter
      * Regular expressions which match the empty string are treated as not matching
      * anything.
      */
-    void setRegExp(const QRegExp& text);
+    void setRegExp(const QRegularExpression& text);
     /** Returns the regular expression which the filter searches for in blocks of text */
-    QRegExp regExp() const;
+    QRegularExpression regExp() const;
 
     /**
      * Reimplemented to search the filter's text buffer for text matching regExp()
@@ -235,7 +235,7 @@ class QTERMWIDGET_EXPORT RegExpFilter : public Filter
                                     int endLine,int endColumn);
 
 private:
-    QRegExp _searchText;
+    QRegularExpression _searchText;
 };
 
 class FilterObject;
@@ -287,11 +287,11 @@ class QTERMWIDGET_EXPORT UrlFilter : public RegExpFilter
 
 private:
 
-    static const QRegExp FullUrlRegExp;
-    static const QRegExp EmailAddressRegExp;
+    static const QRegularExpression FullUrlRegExp;
+    static const QRegularExpression EmailAddressRegExp;
 
     // combined OR of FullUrlRegExp and EmailAddressRegExp
-    static const QRegExp CompleteUrlRegExp;
+    static const QRegularExpression CompleteUrlRegExp;
 signals:
     void activated(const QUrl& url, bool fromContextMenu);
 };
diff --git a/lib/HistorySearch.cpp b/lib/HistorySearch.cpp
index 33c6f4ef..9df3e946 100644
--- a/lib/HistorySearch.cpp
+++ b/lib/HistorySearch.cpp
@@ -24,7 +24,7 @@
 #include "Emulation.h"
 #include "HistorySearch.h"
 
-HistorySearch::HistorySearch(EmulationPtr emulation, const QRegExp& regExp,
+HistorySearch::HistorySearch(EmulationPtr emulation, const QRegularExpression& regExp,
         bool forwards, int startColumn, int startLine,
         QObject* parent) :
 QObject(parent),
@@ -41,7 +41,7 @@ HistorySearch::~HistorySearch() {
 void HistorySearch::search() {
     bool found = false;
 
-    if (! m_regExp.isEmpty())
+    if (! m_regExp.pattern().isEmpty())
     {
         if (m_forwards) {
             found = search(m_startColumn, m_startLine, -1, m_emulation->lineCount()) || search(0, 0, m_startColumn, m_startLine);
@@ -104,22 +104,23 @@ bool HistorySearch::search(int startColumn, int startLine, int endColumn, int en
 
         // So now we can log for m_regExp in the string between startColumn and endPosition
         int matchStart;
+	QRegularExpressionMatch match;
         if (m_forwards)
         {
-            matchStart = string.indexOf(m_regExp, startColumn);
+            matchStart = string.indexOf(m_regExp, startColumn, &match);
             if (matchStart >= endPosition)
                 matchStart = -1;
         }
         else
         {
-            matchStart = string.lastIndexOf(m_regExp, endPosition - 1);
+            matchStart = string.lastIndexOf(m_regExp, endPosition - 1, &match);
             if (matchStart < startColumn)
                 matchStart = -1;
         }
 
         if (matchStart > -1)
         {
-            int matchEnd = matchStart + m_regExp.matchedLength() - 1;
+            int matchEnd = matchStart + match.capturedLength() - 1;
             qDebug() << "Found in string from" << matchStart << "to" << matchEnd;
 
             // Translate startPos and endPos to startColum, startLine, endColumn and endLine in history.
diff --git a/lib/HistorySearch.h b/lib/HistorySearch.h
index 403343d8..9762db24 100644
--- a/lib/HistorySearch.h
+++ b/lib/HistorySearch.h
@@ -22,6 +22,7 @@
 #include <QObject>
 #include <QPointer>
 #include <QMap>
+#include <QRegularExpression>
 
 #include <Session.h>
 #include <ScreenWindow.h>
@@ -38,7 +39,7 @@ class HistorySearch : public QObject
     Q_OBJECT
 
 public:
-    explicit HistorySearch(EmulationPtr emulation, const QRegExp& regExp, bool forwards,
+    explicit HistorySearch(EmulationPtr emulation, const QRegularExpression& regExp, bool forwards,
                            int startColumn, int startLine, QObject* parent);
 
     ~HistorySearch() override;
@@ -55,7 +56,7 @@ class HistorySearch : public QObject
 
 
     EmulationPtr m_emulation;
-    QRegExp m_regExp;
+    QRegularExpression m_regExp;
     bool m_forwards = false;
     int m_startColumn = 0;
     int m_startLine = 0;
diff --git a/lib/KeyboardTranslator.cpp b/lib/KeyboardTranslator.cpp
index e0f28331..2983fdc7 100644
--- a/lib/KeyboardTranslator.cpp
+++ b/lib/KeyboardTranslator.cpp
@@ -34,6 +34,7 @@
 #include <QKeySequence>
 #include <QDir>
 #include <QtDebug>
+#include <QRegularExpression>
 
 #include "tools.h"
 
@@ -353,11 +354,11 @@ bool KeyboardTranslatorReader::decodeSequence(const QString& text,
     KeyboardTranslator::States tempFlags = flags;
     KeyboardTranslator::States tempFlagMask = flagMask;
 
-    for ( int i = 0 ; i < text.count() ; i++ )
+    for ( int i = 0 ; i < text.size() ; i++ )
     {
         const QChar& ch = text[i];
         bool isFirstLetter = i == 0;
-        bool isLastLetter = ( i == text.count()-1 );
+        bool isLastLetter = ( i == text.size()-1 );
         endOfItem = true;
         if ( ch.isLetterOrNumber() )
         {
@@ -453,7 +454,7 @@ bool KeyboardTranslatorReader::parseAsKeyCode(const QString& item , int& keyCode
     QKeySequence sequence = QKeySequence::fromString(item);
     if ( !sequence.isEmpty() )
     {
-        keyCode = sequence[0];
+        keyCode = sequence[0].toCombined();
 
         if ( sequence.count() > 1 )
         {
@@ -539,10 +540,10 @@ QList<KeyboardTranslatorReader::Token> KeyboardTranslatorReader::tokenize(const
     text = text.simplified();
 
     // title line: keyboard "title"
-    static QRegExp title(QLatin1String("keyboard\\s+\"(.*)\""));
+    static QRegularExpression title(QLatin1String("keyboard\\s+\"(.*)\""));
     // key line: key KeySequence : "output"
     // key line: key KeySequence : command
-    static QRegExp key(QLatin1String("key\\s+([\\w\\+\\s\\-\\*\\.]+)\\s*:\\s*(\"(.*)\"|\\w+)"));
+    static QRegularExpression key(QLatin1String("key\\s+([\\w\\+\\s\\-\\*\\.]+)\\s*:\\s*(\"(.*)\"|\\w+)"));
 
     QList<Token> list;
     if ( text.isEmpty() )
@@ -550,30 +551,33 @@ QList<KeyboardTranslatorReader::Token> KeyboardTranslatorReader::tokenize(const
         return list;
     }
 
-    if ( title.exactMatch(text) )
+    const auto titleMatch = title.match(text);
+    const auto keyMatch = key.match(text);
+
+    if ( titleMatch.hasMatch() )
     {
         Token titleToken = { Token::TitleKeyword , QString() };
-        Token textToken = { Token::TitleText , title.capturedTexts().at(1) };
+        Token textToken = { Token::TitleText , titleMatch.captured(1) };
 
         list << titleToken << textToken;
     }
-    else if  ( key.exactMatch(text) )
+    else if  ( keyMatch.hasMatch() )
     {
         Token keyToken = { Token::KeyKeyword , QString() };
-        Token sequenceToken = { Token::KeySequence , key.capturedTexts().value(1).remove(QLatin1Char(' ')) };
+        Token sequenceToken = { Token::KeySequence , keyMatch.captured(1).remove(QLatin1Char(' ')) };
 
         list << keyToken << sequenceToken;
 
-        if ( key.capturedTexts().at(3).isEmpty() )
+        if ( keyMatch.captured(3).isEmpty() )
         {
             // capturedTexts()[2] is a command
-            Token commandToken = { Token::Command , key.capturedTexts().at(2) };
+            Token commandToken = { Token::Command , keyMatch.captured(2) };
             list << commandToken;
         }
         else
         {
             // capturedTexts()[3] is the output string
-           Token outputToken = { Token::OutputText , key.capturedTexts().at(3) };
+           Token outputToken = { Token::OutputText , keyMatch.captured(3) };
            list << outputToken;
         }
     }
@@ -654,7 +658,7 @@ QByteArray KeyboardTranslator::Entry::escapedText(bool expandWildCards,Qt::Keybo
 {
     QByteArray result(text(expandWildCards,modifiers));
 
-    for ( int i = 0 ; i < result.count() ; i++ )
+    for ( int i = 0 ; i < result.size() ; i++ )
     {
         char ch = result[i];
         char replacement = 0;
@@ -676,7 +680,9 @@ QByteArray KeyboardTranslator::Entry::escapedText(bool expandWildCards,Qt::Keybo
 
         if ( replacement == 'x' )
         {
-            result.replace(i,1,"\\x"+QByteArray(1,ch).toHex());
+            QByteArray escaped("\\x");
+            escaped += QByteArray(1,ch).toHex();
+            result.replace(i, 1, QByteArrayView(escaped));
         } else if ( replacement != 0 )
         {
             result.remove(i,1);
@@ -691,10 +697,10 @@ QByteArray KeyboardTranslator::Entry::unescape(const QByteArray& input) const
 {
     QByteArray result(input);
 
-    for ( int i = 0 ; i < result.count()-1 ; i++ )
+    for ( int i = 0 ; i < result.size()-1 ; i++ )
     {
 
-        QByteRef ch = result[i];
+        char ch = result[i];
         if ( ch == '\\' )
         {
            char replacement[2] = {0,0};
@@ -716,9 +722,9 @@ QByteArray KeyboardTranslator::Entry::unescape(const QByteArray& input) const
                     // with the corresponding character value
                     char hexDigits[3] = {0};
 
-                    if ( (i < result.count()-2) && isxdigit(result[i+2]) )
+                    if ( (i < result.size()-2) && isxdigit(result[i+2]) )
                             hexDigits[0] = result[i+2];
-                    if ( (i < result.count()-3) && isxdigit(result[i+3]) )
+                    if ( (i < result.size()-3) && isxdigit(result[i+3]) )
                             hexDigits[1] = result[i+3];
 
                     unsigned charValue = 0;
diff --git a/lib/Pty.cpp b/lib/Pty.cpp
index 75a23a13..46c10280 100644
--- a/lib/Pty.cpp
+++ b/lib/Pty.cpp
@@ -300,7 +300,7 @@ void Pty::sendData(const char* data, int length)
 void Pty::dataReceived()
 {
      QByteArray data = pty()->readAll();
-    emit receivedData(data.constData(),data.count());
+    emit receivedData(data.constData(),data.size());
 }
 
 void Pty::lockPty(bool lock)
@@ -326,9 +326,9 @@ int Pty::foregroundProcessGroup() const
     return 0;
 }
 
-void Pty::setupChildProcess()
+void Pty::onSetupChildProcess()
 {
-    KPtyProcess::setupChildProcess();
+    KPtyProcess::onSetupChildProcess();
 
     // reset all signal handlers
     // this ensures that terminal applications respond to
diff --git a/lib/Pty.h b/lib/Pty.h
index f427a53a..446c1374 100644
--- a/lib/Pty.h
+++ b/lib/Pty.h
@@ -189,7 +189,7 @@ Q_OBJECT
     void receivedData(const char* buffer, int length);
 
   protected:
-      void setupChildProcess() override;
+      void onSetupChildProcess() override;
 
   private slots:
     // called when data is received from the terminal process
diff --git a/lib/SearchBar.cpp b/lib/SearchBar.cpp
index 1de92f45..db0f69bc 100644
--- a/lib/SearchBar.cpp
+++ b/lib/SearchBar.cpp
@@ -18,7 +18,6 @@
 */
 #include <QMenu>
 #include <QAction>
-#include <QRegExp>
 #include <QDebug>
 
 #include "SearchBar.h"
diff --git a/lib/SearchBar.h b/lib/SearchBar.h
index 1200884f..c836f189 100644
--- a/lib/SearchBar.h
+++ b/lib/SearchBar.h
@@ -19,7 +19,7 @@
 #ifndef _SEARCHBAR_H
 #define	_SEARCHBAR_H
 
-#include <QRegExp>
+#include <QRegularExpression>
 
 #include "ui_SearchBar.h"
 #include "HistorySearch.h"
diff --git a/lib/Session.cpp b/lib/Session.cpp
index a40f9986..2d892171 100644
--- a/lib/Session.cpp
+++ b/lib/Session.cpp
@@ -30,13 +30,12 @@
 
 // Qt
 #include <QApplication>
-#include <QByteRef>
 #include <QDir>
 #include <QFile>
-#include <QRegExp>
 #include <QStringList>
 #include <QFile>
 #include <QtDebug>
+#include <QRegularExpression>
 
 #include "Pty.h"
 //#include "kptyprocess.h"
@@ -103,7 +102,7 @@ Session::Session(QObject* parent) :
             this, &Session::cursorChanged);
 
     //connect teletype to emulation backend
-    _shellProcess->setUtf8Mode(_emulation->utf8());
+    _shellProcess->setUtf8Mode(true);
 
     connect( _shellProcess,SIGNAL(receivedData(const char *,int)),this,
              SLOT(onReceiveBlock(const char *,int)) );
@@ -143,11 +142,6 @@ bool Session::isRunning() const
     return _shellProcess->state() == QProcess::Running;
 }
 
-void Session::setCodec(QTextCodec * codec) const
-{
-    emulation()->setCodec(codec);
-}
-
 void Session::setProgram(const QString & program)
 {
     _program = ShellCommand::expand(program);
@@ -381,7 +375,7 @@ void Session::setUserTitle( int what, const QString & caption )
 
     if (what == 31) {
         QString cwd=caption;
-        cwd=cwd.replace( QRegExp(QLatin1String("^~")), QDir::homePath() );
+        cwd=cwd.replace( QRegularExpression(QLatin1String("^~")), QDir::homePath() );
         emit openUrlRequest(cwd);
     }
 
diff --git a/lib/Session.h b/lib/Session.h
index e8b95614..96fea0a8 100644
--- a/lib/Session.h
+++ b/lib/Session.h
@@ -340,9 +340,6 @@ class Session : public QObject {
      */
     void setSize(const QSize & size);
 
-    /** Sets the text codec used by this session's terminal emulation. */
-    void setCodec(QTextCodec * codec) const;
-
     /**
      * Sets whether the session has a dark background or not.  The session
      * uses this information to set the COLORFGBG variable in the process's
diff --git a/lib/ShellCommand.cpp b/lib/ShellCommand.cpp
index 03afa452..46127c9f 100644
--- a/lib/ShellCommand.cpp
+++ b/lib/ShellCommand.cpp
@@ -38,10 +38,10 @@ ShellCommand::ShellCommand(const QString & fullCommand)
 
     QString builder;
 
-    for ( int i = 0 ; i < fullCommand.count() ; i++ ) {
+    for ( int i = 0 ; i < fullCommand.size() ; i++ ) {
         QChar ch = fullCommand[i];
 
-        const bool isLastChar = ( i == fullCommand.count() - 1 );
+        const bool isLastChar = ( i == fullCommand.size() - 1 );
         const bool isQuote = ( ch == QLatin1Char('\'') || ch == QLatin1Char('\"') );
 
         if ( !isLastChar && isQuote ) {
@@ -51,7 +51,7 @@ ShellCommand::ShellCommand(const QString & fullCommand)
                 builder.append(ch);
             }
 
-            if ( (ch.isSpace() && !inQuotes) || ( i == fullCommand.count()-1 ) ) {
+            if ( (ch.isSpace() && !inQuotes) || ( i == fullCommand.size()-1 ) ) {
                 _arguments << builder;
                 builder.clear();
             }
diff --git a/lib/TerminalCharacterDecoder.cpp b/lib/TerminalCharacterDecoder.cpp
index aa13b410..b42010bd 100644
--- a/lib/TerminalCharacterDecoder.cpp
+++ b/lib/TerminalCharacterDecoder.cpp
@@ -75,7 +75,7 @@ void PlainTextDecoder::decodeLine(const Character* const characters, int count,
 
     if (_recordLinePositions && _output->string())
     {
-        int pos = _output->string()->count();
+        int pos = _output->string()->size();
         _linePositions << pos;
     }
 
diff --git a/lib/TerminalDisplay.cpp b/lib/TerminalDisplay.cpp
index 2fb30894..c526eb1c 100644
--- a/lib/TerminalDisplay.cpp
+++ b/lib/TerminalDisplay.cpp
@@ -275,13 +275,7 @@ void TerminalDisplay::setVTFont(const QFont& f)
 {
   QFont font = f;
 
-  // This was originally set for OS X only:
-  //     mac uses floats for font width specification.
-  //     this ensures the same handling for all platforms
-  // but then there was revealed that various Linux distros
-  // have this problem too...
-  font.setStyleStrategy(QFont::ForceIntegerMetrics);
-
+  // Check if font is not fixed pitch and print a warning
   if ( !QFontInfo(font).fixedPitch() )
   {
       qDebug() << "Using a variable-width font in the terminal.  This may cause performance degradation and display/alignment errors.";
@@ -293,10 +287,19 @@ void TerminalDisplay::setVTFont(const QFont& f)
       font.setStyleStrategy( QFont::NoAntialias );
 
   // experimental optimization.  Konsole assumes that the terminal is using a
-  // mono-spaced font, in which case kerning information should have an effect.
+  // mono-spaced font, in which case kerning information should have no effect.
   // Disabling kerning saves some computation when rendering text.
   font.setKerning(false);
 
+  // QFont::ForceIntegerMetrics has been removed.
+  // Set full hinting instead to ensure the letters are aligned properly.
+  font.setHintingPreference(QFont::PreferFullHinting);
+
+  // "Draw intense colors in bold font" feature needs to use different font weights. StyleName
+  // property, when set, doesn't allow weight changes. Since all properties (weight, stretch,
+  // italic, etc) are stored in QFont independently, in almost all cases styleName is not needed.
+  font.setStyleName(QString());
+
   QWidget::setFont(font);
   fontChange(font);
 }
@@ -1619,7 +1622,7 @@ int TerminalDisplay::textWidth(const int startColumn, const int length, const in
   QFontMetrics fm(font());
   int result = 0;
   for (int column = 0; column < length; column++) {
-    result += fm.horizontalAdvance(_image[loc(startColumn + column, line)].character);
+    result += fm.horizontalAdvance(QChar(static_cast<ushort>(_image[loc(startColumn + column, line)].character)));
   }
   return result;
 }
@@ -2126,8 +2129,8 @@ void TerminalDisplay::mouseMoveEvent(QMouseEvent* ev)
 
 //   int distance = KGlobalSettings::dndEventDelay();
    int distance = QApplication::startDragDistance();
-   if ( ev->x() > dragInfo.start.x() + distance || ev->x() < dragInfo.start.x() - distance ||
-        ev->y() > dragInfo.start.y() + distance || ev->y() < dragInfo.start.y() - distance)
+   if ( ev->position().x() > dragInfo.start.x() + distance || ev->position().x() < dragInfo.start.x() - distance ||
+        ev->position().y() > dragInfo.start.y() + distance || ev->position().y() < dragInfo.start.y() - distance)
    {
       // we've left the drag square, we can start a real drag operation now
       emit isBusySelecting(false); // Ok.. we can breath again.
@@ -2221,9 +2224,9 @@ void TerminalDisplay::extendSelection( const QPoint& position )
     QPoint left = left_not_right ? here : _iPntSelCorr;
     i = loc(left.x(),left.y());
     if (i>=0 && i<=_imageSize) {
-      selClass = charClass(_image[i].character);
+      selClass = charClass(QChar(static_cast<ushort>(_image[i].character)));
       while ( ((left.x()>0) || (left.y()>0 && (_lineProperties[left.y()-1] & LINE_WRAPPED) ))
-                      && charClass(_image[i-1].character) == selClass )
+                      && charClass(QChar(static_cast<ushort>(_image[i-1].character))) == selClass )
       { i--; if (left.x()>0) left.rx()--; else {left.rx()=_usedColumns-1; left.ry()--;} }
     }
 
@@ -2231,9 +2234,9 @@ void TerminalDisplay::extendSelection( const QPoint& position )
     QPoint right = left_not_right ? _iPntSelCorr : here;
     i = loc(right.x(),right.y());
     if (i>=0 && i<=_imageSize) {
-      selClass = charClass(_image[i].character);
+      selClass = charClass(QChar(static_cast<ushort>(_image[i].character)));
       while( ((right.x()<_usedColumns-1) || (right.y()<_usedLines-1 && (_lineProperties[right.y()] & LINE_WRAPPED) ))
-                      && charClass(_image[i+1].character) == selClass )
+                      && charClass(QChar(static_cast<ushort>(_image[i-1].character))) == selClass )
       { i++; if (right.x()<_usedColumns-1) right.rx()++; else {right.rx()=0; right.ry()++; } }
     }
 
@@ -2303,7 +2306,7 @@ void TerminalDisplay::extendSelection( const QPoint& position )
     {
       i = loc(right.x(),right.y());
       if (i>=0 && i<=_imageSize) {
-        selClass = charClass(_image[i-1].character);
+        selClass = charClass(QChar(static_cast<ushort>(_image[i-1].character)));
        /* if (selClass == ' ')
         {
           while ( right.x() < _usedColumns-1 && charClass(_image[i+1].character) == selClass && (right.y()<_usedLines-1) &&
@@ -2491,12 +2494,12 @@ void TerminalDisplay::mouseDoubleClickEvent(QMouseEvent* ev)
   _wordSelectionMode = true;
 
   // find word boundaries...
-  QChar selClass = charClass(_image[i].character);
+  QChar selClass = charClass(QChar(static_cast<ushort>(_image[i].character)));
   {
      // find the start of the word
      int x = bgnSel.x();
      while ( ((x>0) || (bgnSel.y()>0 && (_lineProperties[bgnSel.y()-1] & LINE_WRAPPED) ))
-                     && charClass(_image[i-1].character) == selClass )
+                     && charClass(QChar(static_cast<ushort>(_image[i-1].character))) == selClass )
      {
        i--;
        if (x>0)
@@ -2515,7 +2518,7 @@ void TerminalDisplay::mouseDoubleClickEvent(QMouseEvent* ev)
      i = loc( endSel.x(), endSel.y() );
      x = endSel.x();
      while( ((x<_usedColumns-1) || (endSel.y()<_usedLines-1 && (_lineProperties[endSel.y()] & LINE_WRAPPED) ))
-                     && charClass(_image[i+1].character) == selClass )
+                     && charClass(QChar(static_cast<ushort>(_image[i+1].character))) == selClass )
      {
          i++;
          if (x<_usedColumns-1)
@@ -2624,13 +2627,13 @@ void TerminalDisplay::mouseTripleClickEvent(QMouseEvent* ev)
   if (_tripleClickMode == SelectForwardsFromCursor) {
     // find word boundary start
     int i = loc(_iPntSel.x(),_iPntSel.y());
-    QChar selClass = charClass(_image[i].character);
+    QChar selClass = charClass(QChar(static_cast<ushort>(_image[i].character)));
     int x = _iPntSel.x();
 
     while ( ((x>0) ||
              (_iPntSel.y()>0 && (_lineProperties[_iPntSel.y()-1] & LINE_WRAPPED) )
             )
-            && charClass(_image[i-1].character) == selClass )
+            && charClass(QChar(static_cast<ushort>(_image[i-1].character))) == selClass )
     {
         i--;
         if (x>0)
@@ -3320,6 +3323,7 @@ void AutoScrollHandler::timerEvent(QTimerEvent* event)
 
     QMouseEvent mouseEvent(    QEvent::MouseMove,
                               widget()->mapFromGlobal(QCursor::pos()),
+			      QCursor::pos(),
                               Qt::NoButton,
                               Qt::LeftButton,
                               Qt::NoModifier);
diff --git a/lib/Vt102Emulation.cpp b/lib/Vt102Emulation.cpp
index 2a9aa131..f76092d9 100644
--- a/lib/Vt102Emulation.cpp
+++ b/lib/Vt102Emulation.cpp
@@ -31,7 +31,6 @@
 // Qt
 #include <QEvent>
 #include <QKeyEvent>
-#include <QByteRef>
 #include <QDebug>
 
 // Konsole
@@ -45,7 +44,8 @@ Vt102Emulation::Vt102Emulation()
     : Emulation(),
      prevCC(0),
      _titleUpdateTimer(new QTimer(this)),
-     _reportFocusEvents(false)
+     _reportFocusEvents(false),
+     _toUtf8(QStringEncoder::Utf8)
 {
   _titleUpdateTimer->setSingleShot(true);
   QObject::connect(_titleUpdateTimer, &QTimer::timeout,
@@ -72,7 +72,6 @@ void Vt102Emulation::reset()
   _screen[0]->reset();
   resetCharset(1);
   _screen[1]->reset();
-  setCodec(LocaleCodec);
 
   bufferedUpdate();
 }
@@ -512,8 +511,8 @@ void Vt102Emulation::processToken(int token, wchar_t p, int q)
     case TY_ESC_CS('+', 'A') :      setCharset           (3,    'A'); break; //VT100
     case TY_ESC_CS('+', 'B') :      setCharset           (3,    'B'); break; //VT100
 
-    case TY_ESC_CS('%', 'G') :      setCodec             (Utf8Codec   ); break; //LINUX
-    case TY_ESC_CS('%', '@') :      setCodec             (LocaleCodec ); break; //LINUX
+    case TY_ESC_CS('%', 'G') :      /*No longer updating codec*/      break; //LINUX
+    case TY_ESC_CS('%', '@') :      /*No longer updating codec*/      break; //LINUX
 
     case TY_ESC_DE('3'      ) : /* Double height line, top half    */
                                 _currentScreen->setLineProperty( LINE_DOUBLEWIDTH , true );
@@ -954,8 +953,8 @@ void Vt102Emulation::sendMouseEvent( int cb, int cx, int cy , int eventType )
             // coordinate+32, no matter what the locale is. We could easily
             // convert manually, but QString can also do it for us.
             QChar coords[2];
-            coords[0] = cx + 0x20;
-            coords[1] = cy + 0x20;
+            coords[0] = QChar(cx + 0x20);
+            coords[1] = QChar(cy + 0x20);
             QString coordsStr = QString(coords, 2);
             QByteArray utf8 = coordsStr.toUtf8();
             snprintf(command, sizeof(command), "\033[M%c%s", cb + 0x20, utf8.constData());
@@ -1074,7 +1073,9 @@ void Vt102Emulation::sendKeyEvent(QKeyEvent* event, bool fromPaste)
         }
         else if ( !entry.text().isEmpty() )
         {
-            textToSend += _codec->fromUnicode(QString::fromUtf8(entry.text(true,modifiers)));
+	    QString str = QString::fromUtf8(entry.text(true,modifiers));
+	    QByteArray bytes = _toUtf8(str);
+	    textToSend += bytes;
         }
         else if((modifiers & KeyboardTranslator::CTRL_MOD) && event->key() >= 0x40 && event->key() < 0x5f) {
             textToSend += (event->key() & 0x1f);
@@ -1089,7 +1090,8 @@ void Vt102Emulation::sendKeyEvent(QKeyEvent* event, bool fromPaste)
             textToSend += "\033[6~";
         }
         else {
-            textToSend += _codec->fromUnicode(event->text());
+	    QByteArray bytes = _toUtf8(event->text());
+	    textToSend += bytes;
         }
 
         if (!fromPaste && textToSend.length()) {
@@ -1106,7 +1108,7 @@ void Vt102Emulation::sendKeyEvent(QKeyEvent* event, bool fromPaste)
                                          "into characters to send to the terminal "
                                          "is missing.");
         reset();
-        receiveData( translatorError.toUtf8().constData() , translatorError.count() );
+        receiveData( translatorError.toUtf8().constData() , translatorError.size() );
     }
 }
 
@@ -1342,7 +1344,7 @@ char Vt102Emulation::eraseChar() const
                                             Qt::Key_Backspace,
                                             Qt::NoModifier,
                                             KeyboardTranslator::NoState);
-  if ( entry.text().count() > 0 )
+  if ( entry.text().size() > 0 )
       return entry.text().at(0);
   else
       return '\b';
diff --git a/lib/Vt102Emulation.h b/lib/Vt102Emulation.h
index fdbcecd9..524e9cf9 100644
--- a/lib/Vt102Emulation.h
+++ b/lib/Vt102Emulation.h
@@ -193,7 +193,9 @@ private slots:
   QHash<int,QString> _pendingTitleUpdates;
   QTimer* _titleUpdateTimer;
 
-    bool _reportFocusEvents;
+  bool _reportFocusEvents;
+
+  QStringEncoder _toUtf8;
 };
 
 }
diff --git a/lib/kprocess.h b/lib/kprocess.h
index 3dc4616b..1dc370ba 100644
--- a/lib/kprocess.h
+++ b/lib/kprocess.h
@@ -327,8 +327,6 @@ class KProcess : public QProcess
 
 private:
     // hide those
-    using QProcess::setReadChannelMode;
-    using QProcess::readChannelMode;
     using QProcess::setProcessChannelMode;
     using QProcess::processChannelMode;
 };
diff --git a/lib/kpty.cpp b/lib/kpty.cpp
index 544749f0..47f8dc8e 100644
--- a/lib/kpty.cpp
+++ b/lib/kpty.cpp
@@ -511,7 +511,7 @@ void KPty::login(const char * user, const char * remotehost)
 #ifdef HAVE_UTEMPTER
     Q_D(KPty);
 
-    addToUtmp(d->ttyName.constData(), remotehost, d->masterFd);
+    utempter_add_record(d->masterFd, remotehost);
     Q_UNUSED(user)
 #else
 # ifdef HAVE_UTMPX
@@ -597,7 +597,7 @@ void KPty::logout()
 #ifdef HAVE_UTEMPTER
     Q_D(KPty);
 
-    removeLineFromUtmp(d->ttyName.constData(), d->masterFd);
+    utempter_remove_record(d->masterFd);
 #else
     Q_D(KPty);
 
diff --git a/lib/kptyprocess.cpp b/lib/kptyprocess.cpp
index e73ef345..2ccd3bab 100644
--- a/lib/kptyprocess.cpp
+++ b/lib/kptyprocess.cpp
@@ -40,6 +40,9 @@
 KPtyProcess::KPtyProcess(QObject *parent) :
     KPtyProcess(-1, parent)
 {
+    setChildProcessModifier([this](){ 
+        onSetupChildProcess();
+    });
 }
 
 KPtyProcess::KPtyProcess(int ptyMasterFd, QObject *parent) :
@@ -121,7 +124,7 @@ KPtyDevice *KPtyProcess::pty() const
     return d->pty.get();
 }
 
-void KPtyProcess::setupChildProcess()
+void KPtyProcess::onSetupChildProcess()
 {
     Q_D(KPtyProcess);
 
@@ -139,8 +142,6 @@ void KPtyProcess::setupChildProcess()
 
     if (d->ptyChannels & StderrChannel)
         dup2(d->pty->slaveFd(), 2);
-
-    KProcess::setupChildProcess();
 }
 
 //#include "kptyprocess.moc"
diff --git a/lib/kptyprocess.h b/lib/kptyprocess.h
index 4d90823c..ee1234d3 100644
--- a/lib/kptyprocess.h
+++ b/lib/kptyprocess.h
@@ -143,9 +143,9 @@ class KPtyProcess : public KProcess
 
 protected:
     /**
-     * @reimp
+     * Child process configuration
      */
-    void setupChildProcess() override;
+    virtual void onSetupChildProcess();
 
 private:
     std::unique_ptr<KPtyProcessPrivate> const d_ptr;
diff --git a/lib/qtermwidget.cpp b/lib/qtermwidget.cpp
index b7f54346..6f7e707e 100644
--- a/lib/qtermwidget.cpp
+++ b/lib/qtermwidget.cpp
@@ -21,6 +21,7 @@
 #include <QtDebug>
 #include <QDir>
 #include <QMessageBox>
+#include <QRegularExpression>
 
 #include "ColorTables.h"
 #include "Session.h"
@@ -91,8 +92,6 @@ Session *TermWidgetImpl::createSession(QWidget* parent)
     session->setArguments(args);
     session->setAutoClose(true);
 
-    session->setCodec(QTextCodec::codecForName("UTF-8"));
-
     session->setFlowControlEnabled(true);
     session->setHistoryType(HistoryTypeBuffer(1000));
 
@@ -167,9 +166,13 @@ void QTermWidget::search(bool forwards, bool next)
     //qDebug() << "current selection starts at: " << startColumn << startLine;
     //qDebug() << "current cursor position: " << m_impl->m_terminalDisplay->screenWindow()->cursorPosition();
 
-    QRegExp regExp(m_searchBar->searchText());
-    regExp.setPatternSyntax(m_searchBar->useRegularExpression() ? QRegExp::RegExp : QRegExp::FixedString);
-    regExp.setCaseSensitivity(m_searchBar->matchCase() ? Qt::CaseSensitive : Qt::CaseInsensitive);
+    QRegularExpression regExp;
+    if (m_searchBar->useRegularExpression()) {
+        regExp.setPattern(m_searchBar->searchText());
+    } else {
+        regExp.setPattern(QRegularExpression::escape(m_searchBar->searchText()));
+    }
+    regExp.setPatternOptions(m_searchBar->matchCase() ? QRegularExpression::NoPatternOption : QRegularExpression::CaseInsensitiveOption);
 
     HistorySearch *historySearch =
             new HistorySearch(m_impl->m_session->emulation(), regExp, forwards, startColumn, startLine, this);
@@ -266,7 +269,7 @@ void QTermWidget::startTerminalTeletype()
 void QTermWidget::init(int startnow)
 {
     m_layout = new QVBoxLayout();
-    m_layout->setMargin(0);
+    m_layout->setContentsMargins(0,0,0,0);
     setLayout(m_layout);
 
     // translations
@@ -281,7 +284,7 @@ void QTermWidget::init(int startnow)
 
     m_translator = new QTranslator(this);
 
-    for (const QString& dir : qAsConst(dirs)) {
+    for (const QString& dir : std::as_const(dirs)) {
         //qDebug() << "Trying to load translation file from dir" << dir;
         if (m_translator->load(QLocale::system(), QLatin1String("qtermwidget"), QLatin1String(QLatin1String("_")), dir)) {
             qApp->installTranslator(m_translator);
@@ -428,13 +431,6 @@ void QTermWidget::setArgs(const QStringList &args)
     m_impl->m_session->setArguments(args);
 }
 
-void QTermWidget::setTextCodec(QTextCodec *codec)
-{
-    if (!m_impl->m_session)
-        return;
-    m_impl->m_session->setCodec(codec);
-}
-
 void QTermWidget::setColorScheme(const QString& origName)
 {
     const ColorScheme *cs = nullptr;
@@ -836,6 +832,7 @@ void QTermWidget::setWordCharacters(const QString& chars)
     m_impl->m_terminalDisplay->setWordCharacters(chars);
 }
 
+
 QTermWidgetInterface* QTermWidget::createWidget(int startnow) const
 {
    return new QTermWidget(startnow);
diff --git a/lib/qtermwidget.h b/lib/qtermwidget.h
index c5805918..10942dc6 100644
--- a/lib/qtermwidget.h
+++ b/lib/qtermwidget.h
@@ -100,9 +100,6 @@ class QTERMWIDGET_EXPORT QTermWidget : public QWidget, public QTermWidgetInterfa
     // Shell program args, default is none
     void setArgs(const QStringList & args) override;
 
-    //Text codec, default is UTF-8
-    void setTextCodec(QTextCodec * codec) override;
-
     /** @brief Sets the color scheme, default is white on black
      *
      * @param[in] name The name of the color scheme, either returned from
diff --git a/lib/qtermwidget_interface.h b/lib/qtermwidget_interface.h
index 18422798..2ea83af6 100644
--- a/lib/qtermwidget_interface.h
+++ b/lib/qtermwidget_interface.h
@@ -56,7 +56,6 @@ class QTermWidgetInterface {
    virtual void setWorkingDirectory(const QString & dir) = 0;
    virtual QString workingDirectory() = 0;
    virtual void setArgs(const QStringList & args) = 0;
-   virtual void setTextCodec(QTextCodec * codec) = 0;
    virtual void setColorScheme(const QString & name) = 0;
    virtual QStringList getAvailableColorSchemes() = 0;
    virtual void setHistorySize(int lines) = 0;
diff --git a/lib/tools.cpp b/lib/tools.cpp
index 4291fae6..7ca9236c 100644
--- a/lib/tools.cpp
+++ b/lib/tools.cpp
@@ -89,7 +89,7 @@ const QStringList get_color_schemes_dirs()
     }
 #endif
 
-    for (const QString& custom_dir : qAsConst(custom_color_schemes_dirs))
+    for (const QString& custom_dir : std::as_const(custom_color_schemes_dirs))
     {
         d.setPath(custom_dir);
         if (d.exists())
diff --git a/pyqt/project.py b/pyqt/project.py
index 11798c64..cd630518 100644
--- a/pyqt/project.py
+++ b/pyqt/project.py
@@ -11,5 +11,5 @@ def __init__(self, project):
         self._project = project
 
     def apply_user_defaults(self, tool):
-        self.libraries.append('qtermwidget5')
+        self.libraries.append('qtermwidget6')
         super().apply_user_defaults(tool)
diff --git a/pyqt/pyproject.toml b/pyqt/pyproject.toml
index c567f3e1..b6200cf4 100644
--- a/pyqt/pyproject.toml
+++ b/pyqt/pyproject.toml
@@ -6,5 +6,5 @@ build-backend = "sipbuild.api"
 
 [tool.sip.metadata]
 name = "QTermWidget"
-version = "1.4.0"
-requires-dist = ["PyQt5"]
+version = "2.0.0"
+requires-dist = ["PyQt6"]
diff --git a/pyqt/sip/qtermwidget.sip b/pyqt/sip/qtermwidget.sip
index 21a10f8d..e023a781 100644
--- a/pyqt/sip/qtermwidget.sip
+++ b/pyqt/sip/qtermwidget.sip
@@ -47,7 +47,6 @@ public:
     void setWorkingDirectory(const QString & dir);
     QString workingDirectory();
     void setArgs(QStringList & args);
-    void setTextCodec(QTextCodec *codec);
     void setColorScheme(const QString & name);
     QStringList getAvailableColorSchemes();
     static QStringList availableColorSchemes();