diff --git a/quickgui/controller.cpp b/quickgui/controller.cpp
index 181c938..d79b969 100644
--- a/quickgui/controller.cpp
+++ b/quickgui/controller.cpp
@@ -4,6 +4,7 @@
 #include <passwordfile/io/cryptoexception.h>
 #include <passwordfile/io/parsingexception.h>
 
+#include <qtutilities/misc/compat.h>
 #include <qtutilities/misc/dialogutils.h>
 
 #include <c++utilities/io/nativefilestream.h>
@@ -73,9 +74,9 @@ Controller::Controller(QSettings &settings, const QString &filePath, QObject *pa
 void Controller::setFilePath(const QString &filePath)
 {
     // get rid of file:// prefix
-    QStringRef actualFilePath(&filePath);
+    auto actualFilePath = makeStringView(filePath);
     if (filePath.startsWith(QLatin1String("file:"))) {
-        actualFilePath = filePath.midRef(5);
+        actualFilePath = midRef(filePath, 5);
     }
     while (actualFilePath.startsWith(QLatin1String("//"))) {
         actualFilePath = actualFilePath.mid(1);
@@ -483,11 +484,19 @@ void Controller::setUseNativeFileDialog(bool useNativeFileDialog)
 
 void Controller::setEntryFilter(const QString &filter)
 {
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 12, 0))
+    const auto previousFilter(m_entryFilterModel.filterRegularExpression().pattern());
+#else
     const auto previousFilter(m_entryFilterModel.filterRegExp().pattern());
+#endif
     if (filter == previousFilter) {
         return;
     }
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 12, 0))
+    m_entryFilterModel.setFilterRegularExpression(filter);
+#else
     m_entryFilterModel.setFilterRegExp(filter);
+#endif
     emit entryFilterChanged(filter);
     if (previousFilter.isEmpty() != filter.isEmpty()) {
         emit hasEntryFilterChanged(!filter.isEmpty());
diff --git a/quickgui/controller.h b/quickgui/controller.h
index 8cf391d..09f75bc 100644
--- a/quickgui/controller.h
+++ b/quickgui/controller.h
@@ -85,6 +85,7 @@ public:
     QUndoStack *undoStack();
     QString undoText() const;
     QString redoText() const;
+    Io::PasswordFileSaveFlags prepareSaving();
 
 public Q_SLOTS:
     void init();
@@ -101,7 +102,6 @@ public Q_SLOTS:
     void handleFileSelectionCanceled();
     void undo();
     void redo();
-    Io::PasswordFileSaveFlags prepareSaving();
     QString computeFileSummary();
 
 Q_SIGNALS:
@@ -296,12 +296,20 @@ inline QModelIndex Controller::filterEntryIndex(const QModelIndex &entryIndex) c
 
 inline QString Controller::entryFilter() const
 {
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 12, 0))
+    return m_entryFilterModel.filterRegularExpression().pattern();
+#else
     return m_entryFilterModel.filterRegExp().pattern();
+#endif
 }
 
 inline bool Controller::hasEntryFilter() const
 {
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 12, 0))
+    return !m_entryFilterModel.filterRegularExpression().pattern().isEmpty();
+#else
     return !m_entryFilterModel.filterRegExp().isEmpty();
+#endif
 }
 
 inline bool Controller::filterAsDialog() const
diff --git a/quickgui/initiatequick.cpp b/quickgui/initiatequick.cpp
index c82c394..7fd9ed3 100644
--- a/quickgui/initiatequick.cpp
+++ b/quickgui/initiatequick.cpp
@@ -20,7 +20,6 @@
 #include <QQmlApplicationEngine>
 #include <QQmlContext>
 #include <QSettings>
-#include <QTextCodec>
 #include <QtQml>
 #ifdef Q_OS_ANDROID
 #include <QDebug>
@@ -53,7 +52,6 @@ int runQuickGui(int argc, char *argv[], const QtConfigArguments &qtConfigArgs, c
 
     // init application
     SET_QT_APPLICATION_INFO;
-    QGuiApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
 #ifdef PASSWORD_MANAGER_GUI_QTWIDGETS
     QApplication application(argc, argv);
 #else