diff --git a/src/ExtendedTableWidget.cpp b/src/ExtendedTableWidget.cpp
index 73f41c51..5dda16a1 100644
--- a/src/ExtendedTableWidget.cpp
+++ b/src/ExtendedTableWidget.cpp
@@ -25,17 +25,14 @@
 
 #include <limits>
 
-#if QT_VERSION < QT_VERSION_CHECK(5, 4, 0)
-    typedef QList<QByteArray> QByteArrayList;
-#endif
-
-QList<QByteArrayList> ExtendedTableWidget::m_buffer;
+using BufferRow = std::vector<QByteArray>;
+std::vector<BufferRow> ExtendedTableWidget::m_buffer;
 QString ExtendedTableWidget::m_generatorStamp;
 
 namespace
 {
 
-QList<QByteArrayList> parseClipboard(QString clipboard)
+std::vector<BufferRow> parseClipboard(QString clipboard)
 {
     // Remove trailing line break from the clipboard text. This is necessary because some applications append an extra
     // line break to the clipboard contents which we would then interpret as regular data, setting the first field of the
@@ -50,11 +47,11 @@ QList<QByteArrayList> parseClipboard(QString clipboard)
         clipboard.chop(1);
 
     // Make sure there is some data in the clipboard
-    QList<QByteArrayList> result;
+    std::vector<BufferRow> result;
     if(clipboard.isEmpty())
         return result;
 
-    result.push_back(QByteArrayList());
+    result.push_back(BufferRow());
 
     QRegExp re("(\"(?:[^\t\"]+|\"\"[^\"]*\"\")*)\"|(\t|\r?\n)");
     int offset = 0;
@@ -69,7 +66,7 @@ QList<QByteArrayList> parseClipboard(QString clipboard)
             if(QRegExp("\".*\"").exactMatch(text))
                 text = text.mid(1, text.length() - 2);
             text.replace("\"\"", "\"");
-            result.last().push_back(text.toUtf8());
+            result.back().push_back(text.toUtf8());
             break;
         }
 
@@ -81,18 +78,18 @@ QList<QByteArrayList> parseClipboard(QString clipboard)
         QString ws = re.cap(2);
         // if two whitespaces in row - that's an empty cell
         if (!(pos - whitespace_offset)) {
-            result.last().push_back(QByteArray());
+            result.back().push_back(QByteArray());
         } else {
             text = clipboard.mid(whitespace_offset, pos - whitespace_offset);
             if(QRegExp("\".*\"").exactMatch(text))
                 text = text.mid(1, text.length() - 2);
             text.replace("\"\"", "\"");
-            result.last().push_back(text.toUtf8());
+            result.back().push_back(text.toUtf8());
         }
 
         if (ws.endsWith("\n"))
             // create new row
-            result.push_back(QByteArrayList());
+            result.push_back(BufferRow());
 
         whitespace_offset = offset = pos + ws.length();
     }
@@ -440,7 +437,7 @@ void ExtendedTableWidget::copyMimeData(const QModelIndexList& fromIndices, QMime
 
     // Copy selected data into internal copy-paste buffer
     int last_row = indices.first().row();
-    QByteArrayList lst;
+    BufferRow lst;
     for(int i=0;i<indices.size();i++)
     {
         if(indices.at(i).row() != last_row)
@@ -448,7 +445,7 @@ void ExtendedTableWidget::copyMimeData(const QModelIndexList& fromIndices, QMime
             m_buffer.push_back(lst);
             lst.clear();
         }
-        lst << indices.at(i).data(Qt::EditRole).toByteArray();
+        lst.push_back(indices.at(i).data(Qt::EditRole).toByteArray());
         last_row = indices.at(i).row();
     }
     m_buffer.push_back(lst);
@@ -610,10 +607,10 @@ void ExtendedTableWidget::paste()
     // If data in system clipboard is ours and the internal copy-paste buffer is filled, use the internal buffer; otherwise parse the
     // system clipboard contents (case for data copied by other application).
 
-    QList<QByteArrayList> clipboardTable;
-    QList<QByteArrayList>* source;
+    std::vector<BufferRow> clipboardTable;
+    std::vector<BufferRow>* source;
 
-    if(mimeClipboard->hasHtml() && mimeClipboard->html().contains(m_generatorStamp) && !m_buffer.isEmpty())
+    if(mimeClipboard->hasHtml() && mimeClipboard->html().contains(m_generatorStamp) && !m_buffer.empty())
     {
         source = &m_buffer;
     } else {
@@ -626,8 +623,8 @@ void ExtendedTableWidget::paste()
         return;
 
     // Starting from assumption that selection is rectangular, and then first index is upper-left corner and last is lower-right.
-    int rows = source->size();
-    int columns = source->first().size();
+    int rows = static_cast<int>(source->size());
+    int columns = static_cast<int>(source->front().size());
 
     int firstRow = indices.front().row();
     int firstColumn = indices.front().column();
@@ -641,7 +638,7 @@ void ExtendedTableWidget::paste()
     // Special case: if there is only one cell of data to be pasted, paste it into all selected fields
     if(rows == 1 && columns == 1)
     {
-        QByteArray data = source->first().first();
+        QByteArray data = source->front().front();
         for(int row=firstRow;row<firstRow+selectedRows;row++)
         {
             for(int column=firstColumn;column<firstColumn+selectedColumns;column++)
@@ -667,7 +664,7 @@ void ExtendedTableWidget::paste()
 
     // Copy the data cell by cell and as-is from the source buffer to the table
     int row = firstRow;
-    for(const QByteArrayList& source_row : *source)
+    for(const auto& source_row : *source)
     {
         int column = firstColumn;
         for(const QByteArray& source_cell : source_row)
diff --git a/src/ExtendedTableWidget.h b/src/ExtendedTableWidget.h
index 37a82897..86d650f7 100644
--- a/src/ExtendedTableWidget.h
+++ b/src/ExtendedTableWidget.h
@@ -79,8 +79,7 @@ private:
     void useAsFilter(const QString& filterOperator, bool binary = false, const QString& operatorSuffix = "");
     void duplicateUpperCell();
 
-    typedef QList<QByteArray> QByteArrayList;
-    static QList<QByteArrayList> m_buffer;
+    static std::vector<std::vector<QByteArray>> m_buffer;
     static QString m_generatorStamp;
 
 private slots:
diff --git a/src/FileExtensionManager.cpp b/src/FileExtensionManager.cpp
index 808f5517..9d12d587 100644
--- a/src/FileExtensionManager.cpp
+++ b/src/FileExtensionManager.cpp
@@ -1,6 +1,8 @@
 #include "FileExtensionManager.h"
 #include "ui_FileExtensionManager.h"
 
+#include <set>
+
 FileExtensionManager::FileExtensionManager(QStringList init, QWidget *parent) :
     QDialog(parent),
     ui(new Ui::FileExtensionManager)
@@ -46,21 +48,12 @@ void FileExtensionManager::addItem()
 
 void FileExtensionManager::removeItem()
 {
-    QList<int> selectedRows;
+    std::set<int> selectedRows;
     for (const QTableWidgetItem* item : ui->tableExtensions->selectedItems())
-    {
-        if (selectedRows.contains(item->row()) == false)
-        {
-            selectedRows.append(item->row());
-        }
-    }
+        selectedRows.insert(item->row());
 
-    qSort(selectedRows);
-
-    for (int i = selectedRows.size()-1; i >= 0; --i)
-    {
-        ui->tableExtensions->removeRow(selectedRows[i]);
-    }
+    for(int row : selectedRows)
+        ui->tableExtensions->removeRow(row);
 }
 
 void FileExtensionManager::upItem()
diff --git a/src/MainWindow.cpp b/src/MainWindow.cpp
index 276d5f7a..0a55d415 100644
--- a/src/MainWindow.cpp
+++ b/src/MainWindow.cpp
@@ -671,7 +671,7 @@ void MainWindow::populateStructure(const QString& old_table)
 
             sqlb::FieldInfoList fi = jt->fieldInformation();
             for(const sqlb::FieldInfo& f : fi)
-                tablesToColumnsMap[objectname].append(QString::fromStdString(f.name));
+                tablesToColumnsMap[objectname].push_back(QString::fromStdString(f.name));
         }
         qualifiedTablesMap[QString::fromStdString(it.key())] = tablesToColumnsMap;
     }
diff --git a/src/RemoteDatabase.cpp b/src/RemoteDatabase.cpp
index c6bb6b10..5d45bada 100644
--- a/src/RemoteDatabase.cpp
+++ b/src/RemoteDatabase.cpp
@@ -76,7 +76,7 @@ void RemoteDatabase::reloadSettings()
         file.open(QFile::ReadOnly);
         QSslCertificate cert(&file);
         file.close();
-        m_clientCertFiles.insert(path, cert);
+        m_clientCertFiles.insert({path, cert});
     }
 
     // Always add the default certificate for anonymous access to dbhub.io
@@ -85,7 +85,7 @@ void RemoteDatabase::reloadSettings()
         file.open(QFile::ReadOnly);
         QSslCertificate cert(&file);
         file.close();
-        m_clientCertFiles.insert(":/user_certs/public.cert.pem", cert);
+        m_clientCertFiles.insert({":/user_certs/public.cert.pem", cert});
     }
 
     // TODO Add support for proxies here
@@ -200,9 +200,9 @@ void RemoteDatabase::gotReply(QNetworkReply* reply)
                 break;
 
             // Parse data and build licence map (short name -> long name)
-            QMap<std::string, std::string> licences;
+            std::map<std::string, std::string> licences;
             for(auto it=obj.cbegin();it!=obj.cend();++it)
-                licences.insert(it.key(), it.value()["full_name"]);
+                licences.insert({it.key(), it.value()["full_name"]});
 
             // Send licence map to anyone who's interested
             emit gotLicenceList(licences);
@@ -318,7 +318,7 @@ const QList<QSslCertificate>& RemoteDatabase::caCertificates() const
 QString RemoteDatabase::getInfoFromClientCert(const QString& cert, CertInfo info) const
 {
     // Get the common name of the certificate and split it into user name and server address
-    QString cn = m_clientCertFiles[cert].subjectInfo(QSslCertificate::CommonName).at(0);
+    QString cn = m_clientCertFiles.at(cert).subjectInfo(QSslCertificate::CommonName).at(0);
     QStringList cn_parts = cn.split("@");
     if(cn_parts.size() < 2)
         return QString();
diff --git a/src/RemoteDatabase.h b/src/RemoteDatabase.h
index 7c9b3475..0d536271 100644
--- a/src/RemoteDatabase.h
+++ b/src/RemoteDatabase.h
@@ -4,6 +4,8 @@
 #include <QObject>
 #include <QtNetwork/QSslConfiguration>
 
+#include <map>
+
 class QNetworkAccessManager;
 class QNetworkConfigurationManager;
 class QNetworkReply;
@@ -30,7 +32,7 @@ public:
     };
 
     const QList<QSslCertificate>& caCertificates() const;
-    const QMap<QString, QSslCertificate>& clientCertificates() const { return m_clientCertFiles; }
+    const std::map<QString, QSslCertificate>& clientCertificates() const { return m_clientCertFiles; }
     QString getInfoFromClientCert(const QString& cert, CertInfo info) const;
 
     enum RequestType
@@ -61,7 +63,7 @@ signals:
     // a directory listing or the licence list.
     void gotDirList(QString json, QVariant userdata);
     void gotCurrentVersion(QString version, QString url);
-    void gotLicenceList(QMap<std::string, std::string> licences);
+    void gotLicenceList(std::map<std::string, std::string> licences);
     void gotBranchList(std::vector<std::string> branches, std::string default_branch);
 
     // The uploadFinished() signal is emitted when a push() call is finished, i.e. a database upload has completed.
@@ -94,7 +96,7 @@ private:
     QNetworkConfigurationManager* m_configurationManager;
     QProgressDialog* m_progress;
     QSslConfiguration m_sslConfiguration;
-    QMap<QString, QSslCertificate> m_clientCertFiles;
+    std::map<QString, QSslCertificate> m_clientCertFiles;
     sqlite3* m_dbLocal;
 };
 
diff --git a/src/RemoteModel.cpp b/src/RemoteModel.cpp
index b3cc9878..c7c77e72 100644
--- a/src/RemoteModel.cpp
+++ b/src/RemoteModel.cpp
@@ -28,12 +28,12 @@ void RemoteModelItem::setValue(RemoteModelColumns column, QVariant value)
 
 void RemoteModelItem::appendChild(RemoteModelItem *item)
 {
-    m_children.append(item);
+    m_children.push_back(item);
 }
 
 RemoteModelItem* RemoteModelItem::child(int row) const
 {
-    return m_children.value(row);
+    return m_children[static_cast<size_t>(row)];
 }
 
 RemoteModelItem* RemoteModelItem::parent() const
@@ -43,13 +43,19 @@ RemoteModelItem* RemoteModelItem::parent() const
 
 int RemoteModelItem::childCount() const
 {
-    return m_children.count();
+    return static_cast<int>(m_children.size());
 }
 
 int RemoteModelItem::row() const
 {
     if(m_parent)
-        return m_parent->m_children.indexOf(const_cast<RemoteModelItem*>(this));
+    {
+        auto f = std::find( m_parent->m_children.begin(), m_parent->m_children.end(), const_cast<RemoteModelItem*>(this));
+        if(f == m_parent->m_children.end())
+            return -1;
+        else
+            return static_cast<int>(std::distance(m_parent->m_children.begin(), f));
+    }
 
     return 0;
 }
diff --git a/src/RemoteModel.h b/src/RemoteModel.h
index 09b269b7..26d2149e 100644
--- a/src/RemoteModel.h
+++ b/src/RemoteModel.h
@@ -48,7 +48,7 @@ private:
     QVariant m_values[RemoteModelColumnCount];
 
     // Child items and parent item
-    QList<RemoteModelItem*> m_children;
+    std::vector<RemoteModelItem*> m_children;
     RemoteModelItem* m_parent;
 
     // Indicates whether we already tried fetching a directory listing for this item. This serves two purposes:
diff --git a/src/RemotePushDialog.cpp b/src/RemotePushDialog.cpp
index 2badf26b..7245a7e7 100644
--- a/src/RemotePushDialog.cpp
+++ b/src/RemotePushDialog.cpp
@@ -104,15 +104,15 @@ bool RemotePushDialog::forcePush() const
     return ui->checkForce->isChecked();
 }
 
-void RemotePushDialog::fillInLicences(const QMap<std::string, std::string>& licences)
+void RemotePushDialog::fillInLicences(const std::map<std::string, std::string>& licences)
 {
     // Clear licence list and add default item for unspecified licence
     ui->comboLicence->clear();
     ui->comboLicence->addItem(tr("Unspecified"), QString());
 
     // Parse licence list and fill combo box. Show the full name to the user and use the short name as user data.
-    for(auto it=licences.constBegin();it!=licences.constEnd();++it)
-        ui->comboLicence->addItem(QString::fromStdString(it.value()), QString::fromStdString(it.key()));
+    for(const auto& it : licences)
+        ui->comboLicence->addItem(QString::fromStdString(it.second), QString::fromStdString(it.first));
 }
 
 void RemotePushDialog::fillInBranches(const std::vector<std::string>& branches, const std::string& default_branch)
diff --git a/src/RemotePushDialog.h b/src/RemotePushDialog.h
index 5e55c409..3b1b071f 100644
--- a/src/RemotePushDialog.h
+++ b/src/RemotePushDialog.h
@@ -45,7 +45,7 @@ protected slots:
 
     void reloadBranchList();
 
-    void fillInLicences(const QMap<std::string, std::string>& licences);
+    void fillInLicences(const std::map<std::string, std::string>& licences);
     void fillInBranches(const std::vector<std::string>& branches, const std::string& default_branch);
 };
 
diff --git a/src/SqlUiLexer.cpp b/src/SqlUiLexer.cpp
index 5b2747c8..5d6555be 100644
--- a/src/SqlUiLexer.cpp
+++ b/src/SqlUiLexer.cpp
@@ -155,24 +155,24 @@ void SqlUiLexer::setTableNames(const QualifiedTablesMap& tables)
     autocompleteApi->clear();
     listTables.clear();
     setupAutoCompletion();
-    for(auto itSchemas=tables.constBegin();itSchemas!=tables.constEnd();++itSchemas)
+    for(const auto& itSchemas : tables)
     {
-        for(auto itTables=itSchemas.value().constBegin();itTables!=itSchemas.value().constEnd();++itTables)
+        for(const auto& itTables : itSchemas.second)
         {
             // Completion for schema.table
-            autocompleteApi->add(itSchemas.key() + "?" + QString::number(SqlUiLexer::ApiCompleterIconIdSchema) + "." +
-                                 itTables.key() + "?" + QString::number(SqlUiLexer::ApiCompleterIconIdTable));
+            autocompleteApi->add(itSchemas.first + "?" + QString::number(SqlUiLexer::ApiCompleterIconIdSchema) + "." +
+                                 itTables.first + "?" + QString::number(SqlUiLexer::ApiCompleterIconIdTable));
 
-            for(const QString& field : itTables.value()) {
+            for(const QString& field : itTables.second) {
                 // Completion for table.field
-                autocompleteApi->add(itTables.key() + "?" + QString::number(SqlUiLexer::ApiCompleterIconIdTable) + "." +
+                autocompleteApi->add(itTables.first + "?" + QString::number(SqlUiLexer::ApiCompleterIconIdTable) + "." +
                                      field + "?" + QString::number(SqlUiLexer::ApiCompleterIconIdColumn));
 
                 // Completion for isolated field
                 autocompleteApi->add(field + "?" + QString::number(SqlUiLexer::ApiCompleterIconIdColumn));
             }
             // Store the table name list in order to highlight them in a different colour
-            listTables.append(itTables.key());
+            listTables.append(itTables.first);
         }
     }
     autocompleteApi->prepare();
diff --git a/src/SqlUiLexer.h b/src/SqlUiLexer.h
index 1851594f..6cda07e8 100644
--- a/src/SqlUiLexer.h
+++ b/src/SqlUiLexer.h
@@ -3,7 +3,7 @@
 
 #include "Qsci/qscilexersql.h"
 
-#include <QMap>
+#include <map>
 
 class QsciAPIs;
 
@@ -23,8 +23,8 @@ public:
         ApiCompleterIconIdSchema,
     };
 
-    typedef QMap<QString, QList<QString> > TablesAndColumnsMap;
-    typedef QMap<QString, TablesAndColumnsMap > QualifiedTablesMap;
+    using TablesAndColumnsMap = std::map<QString, std::vector<QString>>;
+    using QualifiedTablesMap = std::map<QString, TablesAndColumnsMap>;
 
     void setTableNames(const QualifiedTablesMap& tables);