diff --git a/audio/drivers/alsa.h b/audio/drivers/alsa.h
index 51dd72355845..c78b2999297b 100644
--- a/audio/drivers/alsa.h
+++ b/audio/drivers/alsa.h
@@ -69,12 +69,10 @@ class AlsaDriver
     unsigned int _play_nchan;
     int _play_npfd;
     PollFd _pfd[MAXPFD];
-    snd_pcm_uframes_t _capt_offs;
     snd_pcm_uframes_t _play_offs;
     int _play_step;
     char* _play_ptr[MAXPLAY];
     int _stat;
-    int _pcnt;
     bool _xrun;
     clear_function _clear_func;
     play_function _play_func;
@@ -125,21 +123,21 @@ class AlsaAudio : public Driver
 public:
     AlsaAudio(Seq*);
     virtual ~AlsaAudio();
-    virtual bool init(bool hot = false);
-    virtual bool start(bool hotPlug = false);
-    virtual bool stop();
+    virtual bool init(bool hot = false) override;
+    virtual bool start(bool hotPlug = false) override;
+    virtual bool stop() override;
     float* getLBuffer(long n);
     float* getRBuffer(long n);
     virtual bool isRealtime() const { return false; }
-    virtual void startTransport();
-    virtual void stopTransport();
+    virtual void startTransport() override;
+    virtual void stopTransport() override;
     virtual Transport getState() override;
-    virtual int sampleRate() const;
+    virtual int sampleRate() const override;
     void alsaLoop();
     void write(int n, void* l);
 
-    virtual void midiRead();
-    virtual void updateOutPortCount(int maxport);
+    virtual void midiRead() override;
+    virtual void updateOutPortCount(int maxport) override;
 };
 }
 #endif
diff --git a/audio/drivers/jackaudio.h b/audio/drivers/jackaudio.h
index aabbde32c0cf..8bc70c2fb405 100644
--- a/audio/drivers/jackaudio.h
+++ b/audio/drivers/jackaudio.h
@@ -63,29 +63,29 @@ class JackAudio : public Driver
 public:
     JackAudio(Seq*);
     virtual ~JackAudio();
-    virtual bool init(bool hot = false);
-    virtual bool start(bool hotPlug = false);
-    virtual bool stop();
+    virtual bool init(bool hot = false) override;
+    virtual bool start(bool hotPlug = false) override;
+    virtual bool stop() override;
     int framePos() const;
     void connect(void*, void*);
     void connect(const char* src, const char* dst);
     void disconnect(void* src, void* dst);
     virtual bool isRealtime() const { return jack_is_realtime(client); }
-    virtual void startTransport();
-    virtual void stopTransport();
+    virtual void startTransport() override;
+    virtual void stopTransport() override;
     virtual Transport getState() override;
-    virtual void seekTransport(int);
-    virtual int sampleRate() const { return jack_get_sample_rate(client); }
-    virtual void putEvent(const NPlayEvent&, unsigned framePos);
-    virtual void midiRead();
+    virtual void seekTransport(int) override;
+    virtual int sampleRate() const override { return jack_get_sample_rate(client); }
+    virtual void putEvent(const NPlayEvent&, unsigned framePos) override;
+    virtual void midiRead() override;
 
     virtual void registerPort(const QString& name, bool input, bool midi);
     virtual void unregisterPort(jack_port_t*);
-    virtual void handleTimeSigTempoChanged();
-    virtual void checkTransportSeek(int, int, bool);
-    virtual int bufferSize() { return _segmentSize; }
+    virtual void handleTimeSigTempoChanged() override;
+    virtual void checkTransportSeek(int, int, bool) override;
+    virtual int bufferSize() override { return _segmentSize; }
     void setBufferSize(int nframes) { _segmentSize = nframes; }
-    void updateOutPortCount(int);
+    void updateOutPortCount(int) override;
 };
 } // namespace Ms
 #endif
diff --git a/audio/drivers/pa.h b/audio/drivers/pa.h
index 357743de1818..dc47ec6a4933 100644
--- a/audio/drivers/pa.h
+++ b/audio/drivers/pa.h
@@ -49,16 +49,16 @@ class Portaudio : public Driver
 public:
     Portaudio(Seq*);
     virtual ~Portaudio();
-    virtual bool init(bool hot = false);
-    virtual bool start(bool hotPlug = false);
-    virtual bool stop();
-    virtual void startTransport();
-    virtual void stopTransport();
+    virtual bool init(bool hot = false) override;
+    virtual bool start(bool hotPlug = false) override;
+    virtual bool stop() override;
+    virtual void startTransport() override;
+    virtual void stopTransport() override;
     virtual Transport getState() override;
-    virtual int sampleRate() const { return _sampleRate; }
-    virtual void midiRead();
+    virtual int sampleRate() const override { return _sampleRate; }
+    virtual void midiRead() override;
 #ifdef USE_PORTMIDI
-    virtual void putEvent(const NPlayEvent&, unsigned framePos);
+    virtual void putEvent(const NPlayEvent&, unsigned framePos) override;
 #endif
 
     int framePos() const;
diff --git a/audio/drivers/pulseaudio.cpp b/audio/drivers/pulseaudio.cpp
index 2786c13d62ad..1b3eb359872c 100644
--- a/audio/drivers/pulseaudio.cpp
+++ b/audio/drivers/pulseaudio.cpp
@@ -43,13 +43,13 @@ class PulseAudio : public Driver
 public:
     PulseAudio(Seq*);
     virtual ~PulseAudio();
-    virtual bool init(bool hot = false);
-    virtual bool start(bool hotPlug = false);
-    virtual bool stop();
+    virtual bool init(bool hot = false) override;
+    virtual bool start(bool hotPlug = false) override;
+    virtual bool stop() override;
     virtual Transport getState() override { return state; }
-    virtual int sampleRate() const { return _sampleRate; }
-    virtual void stopTransport() { state = Transport::STOP; }
-    virtual void startTransport() { state = Transport::PLAY; }
+    virtual int sampleRate() const override { return _sampleRate; }
+    virtual void stopTransport() override { state = Transport::STOP; }
+    virtual void startTransport() override { state = Transport::PLAY; }
 };
 
 //---------------------------------------------------------
diff --git a/audio/midi/fluid/fluid.h b/audio/midi/fluid/fluid.h
index 4cd7d8a67c9b..3fa76e82bf51 100644
--- a/audio/midi/fluid/fluid.h
+++ b/audio/midi/fluid/fluid.h
@@ -339,19 +339,19 @@ class Fluid : public Synthesizer
 public:
     Fluid();
     ~Fluid();
-    virtual void init(float sampleRate);
+    virtual void init(float sampleRate) override;
 
-    virtual const char* name() const { return "Fluid"; }
+    virtual const char* name() const override { return "Fluid"; }
 
-    virtual void play(const PlayEvent&);
-    virtual const QList<MidiPatch*>& getPatchInfo() const { return patches; }
+    virtual void play(const PlayEvent&) override;
+    virtual const QList<MidiPatch*>& getPatchInfo() const override { return patches; }
 
     // get/set synthesizer state (parameter set)
-    virtual SynthesizerGroup state() const;
-    virtual bool setState(const SynthesizerGroup&);
+    virtual SynthesizerGroup state() const override;
+    virtual bool setState(const SynthesizerGroup&) override;
 
-    virtual void allSoundsOff(int);
-    virtual void allNotesOff(int);
+    virtual void allSoundsOff(int) override;
+    virtual void allNotesOff(int) override;
 
     int loadProgress() { return _loadProgress; }
     void setLoadProgress(int val) { _loadProgress = val; }
@@ -383,9 +383,9 @@ class Fluid : public Synthesizer
 
     Preset* get_channel_preset(int chan) const { return channel[chan]->preset(); }
 
-    virtual bool loadSoundFonts(const QStringList& s);
-    virtual bool addSoundFont(const QString& s);
-    virtual bool removeSoundFont(const QString& s);
+    virtual bool loadSoundFonts(const QStringList& s) override;
+    virtual bool addSoundFont(const QString& s) override;
+    virtual bool removeSoundFont(const QString& s) override;
     QStringList soundFonts() const;
     std::vector<SoundFontInfo> soundFontsInfo() const override;
 
@@ -393,7 +393,7 @@ class Fluid : public Synthesizer
     Voice* alloc_voice(unsigned id, Sample* sample, int chan, int key, int vel, double vt);
     void free_voice_by_kill();
 
-    virtual void process(unsigned len, float* out, float* effect1, float* effect2);
+    virtual void process(unsigned len, float* out, float* effect1, float* effect2) override;
 
     bool program_select(int chan, unsigned sfont_id, unsigned bank_num, unsigned preset_num);
     void get_program(int chan, unsigned* sfont_id, unsigned* bank_num, unsigned* preset_num);
@@ -412,12 +412,12 @@ class Fluid : public Synthesizer
     float act2hz(float c) { return 8.176 * pow(2.0, (double)c / 1200.0); }
     float ct2hz(float cents) { return act2hz(qBound(1500.0f, cents, 13500.0f)); }
 
-    virtual double masterTuning() const { return _masterTuning; }
-    virtual void setMasterTuning(double f) { _masterTuning = f; }
+    virtual double masterTuning() const override { return _masterTuning; }
+    virtual void setMasterTuning(double f) override { _masterTuning = f; }
 
     QString error() const { return _error; }
 
-    virtual SynthesizerGui* gui();
+    virtual SynthesizerGui* gui() override;
 
     static QFileInfoList sfFiles();
 
diff --git a/audio/midi/zerberus/zerberus.h b/audio/midi/zerberus/zerberus.h
index 494146cde27b..caad9184eb89 100644
--- a/audio/midi/zerberus/zerberus.h
+++ b/audio/midi/zerberus/zerberus.h
@@ -106,8 +106,8 @@ class Zerberus : public Ms::Synthesizer
     Zerberus();
     ~Zerberus();
 
-    virtual void process(unsigned frames, float*, float*, float*);
-    virtual void play(const Ms::PlayEvent& event);
+    virtual void process(unsigned frames, float*, float*, float*) override;
+    virtual void play(const Ms::PlayEvent& event) override;
 
     bool loadInstrument(const QString&);
 
@@ -119,22 +119,22 @@ class Zerberus : public Ms::Synthesizer
     bool loadWasCanceled() { return _loadWasCanceled; }
     void setLoadWasCanceled(bool status) { _loadWasCanceled = status; }
 
-    virtual void setMasterTuning(double val) { _masterTuning = val; }
-    virtual double masterTuning() const { return _masterTuning; }
+    virtual void setMasterTuning(double val) override { _masterTuning = val; }
+    virtual double masterTuning() const override { return _masterTuning; }
 
     double ct2hz(double c) const { return pow(2.0, (c - 6900.0) / 1200.0) * masterTuning(); }
 
-    virtual const char* name() const;
+    virtual const char* name() const override;
 
-    virtual Ms::SynthesizerGroup state() const;
-    virtual bool setState(const Ms::SynthesizerGroup&);
+    virtual Ms::SynthesizerGroup state() const override;
+    virtual bool setState(const Ms::SynthesizerGroup&) override;
 
-    virtual void allSoundsOff(int channel);
-    virtual void allNotesOff(int channel);
+    virtual void allSoundsOff(int channel) override;
+    virtual void allNotesOff(int channel) override;
 
-    virtual bool addSoundFont(const QString&);
-    virtual bool removeSoundFont(const QString&);
-    virtual bool loadSoundFonts(const QStringList&);
+    virtual bool addSoundFont(const QString&) override;
+    virtual bool removeSoundFont(const QString&) override;
+    virtual bool loadSoundFonts(const QStringList&) override;
     virtual bool removeSoundFonts(const QStringList& fileNames);
     QStringList soundFonts() const;
     std::vector<Ms::SoundFontInfo> soundFontsInfo() const override;
@@ -143,7 +143,7 @@ class Zerberus : public Ms::Synthesizer
 
     void updatePatchList();
 
-    virtual Ms::SynthesizerGui* gui();
+    virtual Ms::SynthesizerGui* gui() override;
     static QFileInfoList sfzFiles();
 };
 
diff --git a/framework/audio/internal/rpcmidisource.cpp b/framework/audio/internal/rpcmidisource.cpp
index 70254b483f6f..bfacb64ef7f1 100644
--- a/framework/audio/internal/rpcmidisource.cpp
+++ b/framework/audio/internal/rpcmidisource.cpp
@@ -28,7 +28,7 @@ using namespace mu::audio::worker;
 RpcMidiSource::RpcMidiSource(const std::string& name)
     : RpcSourceBase(CallType::Midi, name)
 {
-    listen([this](const CallMethod& /*method*/, const Args& /*args*/) {});
+    listen([](const CallMethod& /*method*/, const Args& /*args*/) {});
 }
 
 std::shared_ptr<IAudioSource> RpcMidiSource::audioSource()
diff --git a/framework/midi/internal/sequencer.h b/framework/midi/internal/sequencer.h
index 68cc570de877..7608c7496953 100644
--- a/framework/midi/internal/sequencer.h
+++ b/framework/midi/internal/sequencer.h
@@ -52,7 +52,7 @@ class Sequencer : public ISequencer, public async::Asyncable
 
     Status status() const;
 
-    void loadMIDI(const std::shared_ptr<midi::MidiStream>& stream);
+    void loadMIDI(const std::shared_ptr<midi::MidiStream>& stream) override;
 
     bool run(float init_sec) override;
     void seek(float sec) override;
diff --git a/framework/midi/internal/zerberus/zerberus.h b/framework/midi/internal/zerberus/zerberus.h
index 0bdbb2e3a032..90fd178b61c3 100644
--- a/framework/midi/internal/zerberus/zerberus.h
+++ b/framework/midi/internal/zerberus/zerberus.h
@@ -86,7 +86,6 @@ class Zerberus //: public Ms::Synthesizer
     std::list<ZInstrument*> instruments;
     Channel* _channel[MAX_CHANNELS];
 
-    int allocatedVoices = 0;
     VoiceFifo freeVoices;
     Voice* activeVoices = 0;
     int _loadProgress = 0;
diff --git a/framework/ui/qml/MuseScore/Ui/InteractiveProvider.qml b/framework/ui/qml/MuseScore/Ui/InteractiveProvider.qml
index 863b94c51065..34d0166df453 100644
--- a/framework/ui/qml/MuseScore/Ui/InteractiveProvider.qml
+++ b/framework/ui/qml/MuseScore/Ui/InteractiveProvider.qml
@@ -21,7 +21,7 @@ Item {
     Connections {
         target: root.provider
 
-        onFireOpen: {
+        function onFireOpen(data) {
 
             var page = data.data()
             console.log("try open uri: " + data.value("uri") + ", page: " + JSON.stringify(page))
diff --git a/framework/uicomponents/qml/MuseScore/UiComponents/SeparatorLine.qml b/framework/uicomponents/qml/MuseScore/UiComponents/SeparatorLine.qml
index 9b85d699e515..05ca0cd155bb 100644
--- a/framework/uicomponents/qml/MuseScore/UiComponents/SeparatorLine.qml
+++ b/framework/uicomponents/qml/MuseScore/UiComponents/SeparatorLine.qml
@@ -1,4 +1,6 @@
-import QtQuick 2.0
+import QtQuick 2.9
+import QtQuick.Layouts 1.3
+
 import MuseScore.Ui 1.0
 
 Rectangle {
@@ -13,15 +15,10 @@ Rectangle {
             name: "HORIZONTAL"
             when: orientation == Qt.Horizontal
 
-            AnchorChanges {
-                target: root
-                anchors.left: parent.left
-                anchors.right: parent.right
-            }
-
             PropertyChanges {
                 target: root
                 height: 1
+                Layout.fillWidth: true
             }
         },
 
@@ -29,15 +26,10 @@ Rectangle {
             name: "VERTICAL"
             when: orientation == Qt.Vertical
 
-            AnchorChanges {
-                target: root
-                anchors.top: parent.top
-                anchors.bottom: parent.bottom
-            }
-
             PropertyChanges {
                 target: root
                 width: 1
+                Layout.fillHeight: true
             }
         }
     ]
diff --git a/framework/uicomponents/qml/MuseScore/UiComponents/TabPanel.qml b/framework/uicomponents/qml/MuseScore/UiComponents/TabPanel.qml
index 54a5d2575723..ba76ee805f4f 100644
--- a/framework/uicomponents/qml/MuseScore/UiComponents/TabPanel.qml
+++ b/framework/uicomponents/qml/MuseScore/UiComponents/TabPanel.qml
@@ -23,7 +23,7 @@ TabView {
         Connections {
             target: root
 
-            onCurrentIndexChanged: {
+            function onCurrentIndexChanged(currentIndex) {
                 if (currentIndex < 0)
                     return
 
diff --git a/libmscore/ambitus.h b/libmscore/ambitus.h
index f2044e8aaa50..8119b45879ec 100644
--- a/libmscore/ambitus.h
+++ b/libmscore/ambitus.h
@@ -95,9 +95,9 @@ class Ambitus final : public Element
     QString   accessibleInfo() const override;
 
     // properties
-    QVariant getProperty(Pid) const;
-    bool setProperty(Pid propertyId, const QVariant&);
-    QVariant propertyDefault(Pid id) const;
+    QVariant getProperty(Pid) const override;
+    bool setProperty(Pid propertyId, const QVariant&) override;
+    QVariant propertyDefault(Pid id) const override;
 
     Element* nextSegmentElement() override;
     Element* prevSegmentElement() override;
diff --git a/libmscore/arpeggio.h b/libmscore/arpeggio.h
index 725df58d7076..be1b0946a7c9 100644
--- a/libmscore/arpeggio.h
+++ b/libmscore/arpeggio.h
@@ -76,7 +76,7 @@ class Arpeggio final : public Element
 
     int span() const { return _span; }
     void setSpan(int val) { _span = val; }
-    void setHeight(qreal);
+    void setHeight(qreal) override;
 
     qreal userLen1() const { return _userLen1; }
     qreal userLen2() const { return _userLen2; }
diff --git a/libmscore/articulation.h b/libmscore/articulation.h
index 822a1e7e2b2b..e2931560cab1 100644
--- a/libmscore/articulation.h
+++ b/libmscore/articulation.h
@@ -70,7 +70,7 @@ class Articulation final : public Element
     MScore::OrnamentStyle _ornamentStyle;       // for use in ornaments such as trill
     bool _playArticulation;
 
-    void draw(QPainter*) const;
+    void draw(QPainter*) const override;
 
     enum class AnchorGroup {
         ARTICULATION,
@@ -92,7 +92,7 @@ class Articulation final : public Element
     SymId symId() const { return _symId; }
     void setSymId(SymId id);
     int subtype() const override;
-    QString userName() const;
+    QString userName() const override;
     const char* articulationName() const;    // type-name of articulation; used for midi rendering
     static const char* symId2ArticulationName(SymId symId);
 
diff --git a/libmscore/barline.h b/libmscore/barline.h
index 4470a3ef234c..ebb66959817d 100644
--- a/libmscore/barline.h
+++ b/libmscore/barline.h
@@ -68,7 +68,7 @@ class BarLine final : public Element
     void drawTips(QPainter* painter, bool reversed, qreal x) const;
     bool isTop() const;
     bool isBottom() const;
-    void drawEditMode(QPainter*, EditData&);
+    void drawEditMode(QPainter*, EditData&) override;
 
 public:
     BarLine(Score* s = 0);
@@ -138,7 +138,7 @@ class BarLine final : public Element
     bool setProperty(Pid propertyId, const QVariant&) override;
     QVariant propertyDefault(Pid propertyId) const override;
     Pid propertyId(const QStringRef& xmlName) const override;
-    void undoChangeProperty(Pid id, const QVariant&, PropertyFlags ps);
+    void undoChangeProperty(Pid id, const QVariant&, PropertyFlags ps) override;
     using ScoreElement::undoChangeProperty;
 
     static qreal layoutWidth(Score*, BarLineType);
diff --git a/libmscore/beam.h b/libmscore/beam.h
index 1bdb4c7cd77d..5fdce1f87464 100644
--- a/libmscore/beam.h
+++ b/libmscore/beam.h
@@ -112,7 +112,7 @@ class Beam final : public Element
 
     void layout1();
     void layoutGraceNotes();
-    void layout();
+    void layout() override;
 
     const QVector<ChordRest*>& elements() const { return _elements; }
     void clear() { _elements.clear(); }
diff --git a/libmscore/bsymbol.h b/libmscore/bsymbol.h
index 6a4a593533d6..69f4ca950380 100644
--- a/libmscore/bsymbol.h
+++ b/libmscore/bsymbol.h
@@ -44,8 +44,8 @@ class BSymbol : public Element
     virtual void layout() override;
     virtual QRectF drag(EditData&) override;
 
-    void writeProperties(XmlWriter& xml) const;
-    bool readProperties(XmlReader&);
+    void writeProperties(XmlWriter& xml) const override;
+    bool readProperties(XmlReader&) override;
 
     Align align() const { return _align; }
     void setAlign(Align a) { _align = a; }
diff --git a/libmscore/chordrest.h b/libmscore/chordrest.h
index 69ec7800af4b..66ad1f0f21ee 100644
--- a/libmscore/chordrest.h
+++ b/libmscore/chordrest.h
@@ -73,8 +73,6 @@ class ChordRest : public DurationElement
     ChordRest& operator=(const ChordRest&) = delete;
     ~ChordRest();
 
-    virtual ElementType type() const = 0;
-
     // Score Tree functions
     virtual ScoreElement* treeParent() const override;
     virtual ScoreElement* treeChild(int idx) const override;
@@ -84,10 +82,9 @@ class ChordRest : public DurationElement
     virtual void undoUnlink() override;
 
     virtual Segment* segment() const { return (Segment*)parent(); }
-    virtual Measure* measure() const = 0;
 
-    virtual void writeProperties(XmlWriter& xml) const;
-    virtual bool readProperties(XmlReader&);
+    virtual void writeProperties(XmlWriter& xml) const override;
+    virtual bool readProperties(XmlReader&) override;
     virtual void readAddConnector(ConnectorInfoReader* info, bool pasteMode) override;
 
     void setBeamMode(Beam::Mode m) { _beamMode = m; }
@@ -155,8 +152,8 @@ class ChordRest : public DurationElement
     bool isMelismaEnd() const;
     void setMelismaEnd(bool v);
 
-    virtual void add(Element*);
-    virtual void remove(Element*);
+    virtual void add(Element*) override;
+    virtual void remove(Element*) override;
     void removeDeleteBeam(bool beamed);
     void replaceBeam(Beam* newBeam);
 
diff --git a/libmscore/element.h b/libmscore/element.h
index 86e9ee3d6d0a..48fa8e9b8647 100644
--- a/libmscore/element.h
+++ b/libmscore/element.h
@@ -617,7 +617,6 @@ class Compound : public Element
 public:
     Compound(Score*);
     Compound(const Compound&);
-    virtual ElementType type() const = 0;
 
     virtual void draw(QPainter*) const;
     virtual void addElement(Element*, qreal x, qreal y);
diff --git a/libmscore/fermata.h b/libmscore/fermata.h
index 22997017ccc4..7a96fbf18015 100644
--- a/libmscore/fermata.h
+++ b/libmscore/fermata.h
@@ -51,7 +51,7 @@ class Fermata final : public Element
     SymId symId() const { return _symId; }
     void setSymId(SymId id) { _symId  = id; }
     int subtype() const override;
-    QString userName() const;
+    QString userName() const override;
 
     void layout() override;
 
diff --git a/libmscore/lasso.h b/libmscore/lasso.h
index f09ce93ebb2f..25549437b858 100644
--- a/libmscore/lasso.h
+++ b/libmscore/lasso.h
@@ -29,7 +29,7 @@ class Lasso : public Element
     virtual void draw(QPainter*) const override;
     virtual bool isEditable() const override { return true; }
     virtual void editDrag(EditData&) override;
-    virtual void endDrag(EditData&) {}
+    virtual void endDrag(EditData&) override {}
 
     virtual QVariant getProperty(Pid propertyId) const override;
     virtual bool setProperty(Pid propertyId, const QVariant&) override;
diff --git a/libmscore/line.h b/libmscore/line.h
index 9f6ce364b9fc..e7024fce384a 100644
--- a/libmscore/line.h
+++ b/libmscore/line.h
@@ -45,14 +45,13 @@ class LineSegment : public SpannerSegment
     LineSegment(Score* s, ElementFlags f = ElementFlag::NOTHING)
         : SpannerSegment(s, f) {}
     LineSegment(const LineSegment&);
-    virtual void draw(QPainter*) const = 0;
     SLine* line() const { return (SLine*)spanner(); }
     virtual void spatiumChanged(qreal, qreal) override;
     virtual void localSpatiumChanged(qreal, qreal) override;
 
     friend class SLine;
     virtual void read(XmlReader&) override;
-    bool readProperties(XmlReader&);
+    bool readProperties(XmlReader&) override;
 
     virtual Element* propertyDelegate(Pid) override;
 
@@ -100,8 +99,8 @@ class SLine : public Spanner
     virtual void layout() override;
     virtual SpannerSegment* layoutSystem(System*) override;
 
-    bool readProperties(XmlReader& node);
-    void writeProperties(XmlWriter& xml) const;
+    bool readProperties(XmlReader& node) override;
+    void writeProperties(XmlWriter& xml) const override;
     virtual LineSegment* createLineSegment() = 0;
     void setLen(qreal l);
     using Element::bbox;
diff --git a/libmscore/measure.h b/libmscore/measure.h
index c3a7a5f2be06..f49b15b53b26 100644
--- a/libmscore/measure.h
+++ b/libmscore/measure.h
@@ -160,10 +160,10 @@ class Measure final : public MeasureBase
     int treeChildCount() const override;
 
     void read(XmlReader&, int idx);
-    void read(XmlReader& d) { read(d, 0); }
+    void read(XmlReader& d) override { read(d, 0); }
     void readAddConnector(ConnectorInfoReader* info, bool pasteMode) override;
     void write(XmlWriter& xml) const override { Element::write(xml); }
-    void write(XmlWriter&, int, bool writeSystemElements, bool forceTimeSig) const;
+    void write(XmlWriter&, int, bool writeSystemElements, bool forceTimeSig) const override;
     void writeBox(XmlWriter&) const;
     void readBox(XmlReader&);
     bool isEditable() const override { return false; }
@@ -327,7 +327,7 @@ class Measure final : public MeasureBase
     qreal basicStretch() const;
     qreal basicWidth() const;
     int layoutWeight(int maxMMRestLength = 0) const;
-    void computeMinWidth();
+    void computeMinWidth() override;
     void checkHeader();
     void checkTrailer();
     void setStretchedWidth(qreal);
diff --git a/libmscore/measurebase.h b/libmscore/measurebase.h
index befd07990a38..bf11813dcb41 100644
--- a/libmscore/measurebase.h
+++ b/libmscore/measurebase.h
@@ -85,9 +85,6 @@ class MeasureBase : public Element
     ScoreElement* treeChild(int idx) const override;
     int treeChildCount() const override;
 
-    virtual MeasureBase* clone() const = 0;
-    virtual ElementType type() const = 0;
-
     virtual void setScore(Score* s) override;
 
     MeasureBase* next() const { return _next; }
@@ -106,7 +103,7 @@ class MeasureBase : public Element
     virtual void write(XmlWriter&) const override = 0;
     virtual void write(XmlWriter&, int, bool, bool) const = 0;
 
-    virtual void layout();
+    virtual void layout() override;
 
     ElementList& el() { return _el; }
     const ElementList& el() const { return _el; }
diff --git a/libmscore/mmrest.h b/libmscore/mmrest.h
index 11b6ac198813..c304efc8098a 100644
--- a/libmscore/mmrest.h
+++ b/libmscore/mmrest.h
@@ -37,8 +37,8 @@ class MMRest final : public Rest
 
     void draw(QPainter*) const override;
     void layout() override;
-    void setWidth(qreal width) { m_width = width; }
-    qreal width() const { return m_width; }
+    void setWidth(qreal width) override { m_width = width; }
+    qreal width() const override { return m_width; }
     QRectF numberRect() const;
 
     void write(XmlWriter&) const override;
diff --git a/libmscore/rest.h b/libmscore/rest.h
index 37c190c7555e..82c4fc6d49b1 100644
--- a/libmscore/rest.h
+++ b/libmscore/rest.h
@@ -48,7 +48,7 @@ class Rest : public ChordRest
 
     void draw(QPainter*) const override;
     void scanElements(void* data, void (* func)(void*, Element*), bool all = true) override;
-    void setTrack(int val);
+    void setTrack(int val) override;
 
     bool acceptDrop(EditData&) const override;
     Element* drop(EditData&) override;
@@ -59,8 +59,8 @@ class Rest : public ChordRest
 
     void reset() override;
 
-    virtual void add(Element*);
-    virtual void remove(Element*);
+    virtual void add(Element*) override;
+    virtual void remove(Element*) override;
 
     void read(XmlReader&) override;
     void write(XmlWriter& xml) const override;
@@ -77,16 +77,16 @@ class Rest : public ChordRest
     void setAccent(bool flag);
     int computeLineOffset(int lines);
 
-    virtual int upLine() const;
-    virtual int downLine() const;
-    virtual QPointF stemPos() const;
-    virtual qreal stemPosX() const;
-    virtual QPointF stemPosBeam() const;
+    virtual int upLine() const override;
+    virtual int downLine() const override;
+    virtual QPointF stemPos() const override;
+    virtual qreal stemPosX() const override;
+    virtual QPointF stemPosBeam() const override;
     virtual qreal rightEdge() const override;
 
     void localSpatiumChanged(qreal oldValue, qreal newValue) override;
     QVariant propertyDefault(Pid) const override;
-    void resetProperty(Pid id);
+    void resetProperty(Pid id) override;
     bool setProperty(Pid propertyId, const QVariant& v) override;
     QVariant getProperty(Pid propertyId) const override;
     void undoChangeDotsVisible(bool v);
diff --git a/libmscore/score.cpp b/libmscore/score.cpp
index 840834553fae..1b93d779f6e9 100644
--- a/libmscore/score.cpp
+++ b/libmscore/score.cpp
@@ -2221,7 +2221,7 @@ bool Score::appendMeasuresFromScore(Score* score, const Fraction& startTick, con
             curTick += nm->ticks();
             nmb = toMeasureBase(nm);
         } else {
-            nmb = cmb->clone();
+            nmb = static_cast<MeasureBase*>(cmb->clone());
         }
 
         addMeasure(nmb, 0);
diff --git a/libmscore/score.h b/libmscore/score.h
index 8f70e8d39cfb..7495fdee0a1a 100644
--- a/libmscore/score.h
+++ b/libmscore/score.h
@@ -975,7 +975,7 @@ class Score : public QObject, public ScoreElement
     void setInputTrack(int t) { inputState().setTrack(t); }
 
     void spatiumChanged(qreal oldValue, qreal newValue);
-    void styleChanged();
+    void styleChanged() override;
 
     void cmdPaste(const QMimeData* ms, MuseScoreView* view, Fraction scale = Fraction(1, 1));
     bool pasteStaff(XmlReader&, Segment* dst, int staffIdx, Fraction scale = Fraction(1, 1));
diff --git a/libmscore/slurtie.h b/libmscore/slurtie.h
index a78d8597d080..4b79b7ed037c 100644
--- a/libmscore/slurtie.h
+++ b/libmscore/slurtie.h
@@ -119,7 +119,7 @@ class SlurTieSegment : public SpannerSegment
     std::vector<QPointF> gripsPositions(const EditData& = EditData()) const override;
 
     void writeSlur(XmlWriter& xml, int no) const;
-    void read(XmlReader&);
+    void read(XmlReader&) override;
     virtual void drawEditMode(QPainter*, EditData&) override;
     virtual void computeBezier(QPointF so = QPointF()) = 0;
 };
@@ -146,7 +146,6 @@ class SlurTie : public Spanner
     SlurTie(const SlurTie&);
     ~SlurTie();
 
-    virtual ElementType type() const = 0;
     bool up() const { return _up; }
 
     virtual void reset() override;
@@ -160,8 +159,8 @@ class SlurTie : public Spanner
 
     virtual void read(XmlReader&) override;
 
-    void writeProperties(XmlWriter& xml) const;
-    bool readProperties(XmlReader&);
+    void writeProperties(XmlWriter& xml) const override;
+    bool readProperties(XmlReader&) override;
 
     int lineType() const { return _lineType; }
     void setLineType(int val) { _lineType = val; }
diff --git a/libmscore/spanner.h b/libmscore/spanner.h
index 09678d4a6238..c46a2f8b65bc 100644
--- a/libmscore/spanner.h
+++ b/libmscore/spanner.h
@@ -44,7 +44,6 @@ class SpannerSegment : public Element
     SpannerSegment(Spanner*, Score*, ElementFlags f = ElementFlag::ON_STAFF | ElementFlag::MOVABLE);
     SpannerSegment(Score* s, ElementFlags f = ElementFlag::ON_STAFF | ElementFlag::MOVABLE);
     SpannerSegment(const SpannerSegment&);
-    virtual SpannerSegment* clone() const = 0;
 
     // Score Tree functions
     virtual ScoreElement* treeParent() const override;
@@ -174,7 +173,6 @@ class Spanner : public Element
 
     virtual qreal mag() const override;
 
-    virtual ElementType type() const = 0;
     virtual void setScore(Score* s) override;
 
     bool readProperties(XmlReader&) override;
@@ -227,9 +225,9 @@ class Spanner : public Element
     virtual void removeUnmanaged();
     virtual void insertTimeUnmanaged(const Fraction& tick, const Fraction& len);
 
-    QVariant getProperty(Pid propertyId) const;
-    bool setProperty(Pid propertyId, const QVariant& v);
-    QVariant propertyDefault(Pid propertyId) const;
+    QVariant getProperty(Pid propertyId) const override;
+    bool setProperty(Pid propertyId, const QVariant& v) override;
+    QVariant propertyDefault(Pid propertyId) const override;
     virtual void undoChangeProperty(Pid id, const QVariant&, PropertyFlags ps) override;
 
     void computeStartElement();
diff --git a/libmscore/staff.h b/libmscore/staff.h
index 1e943ce422dd..9bc988bd4de6 100644
--- a/libmscore/staff.h
+++ b/libmscore/staff.h
@@ -119,9 +119,9 @@ class Staff final : public Element
     QString partName() const;
     int rstaff() const;
     int idx() const;
-    void read(XmlReader&);
-    bool readProperties(XmlReader&);
-    void write(XmlWriter& xml) const;
+    void read(XmlReader&) override;
+    bool readProperties(XmlReader&) override;
+    void write(XmlWriter& xml) const override;
     Part* part() const { return _part; }
     void setPart(Part* p) { _part = p; }
 
@@ -191,7 +191,7 @@ class Staff final : public Element
     void setBarLineSpan(int val) { _barLineSpan = val; }
     void setBarLineFrom(int val) { _barLineFrom = val; }
     void setBarLineTo(int val) { _barLineTo = val; }
-    qreal height() const;
+    qreal height() const override;
 
     int channel(const Fraction&, int voice) const;
 
@@ -252,13 +252,13 @@ class Staff final : public Element
     qreal userDist() const { return _userDist; }
     void setUserDist(qreal val) { _userDist = val; }
 
-    void spatiumChanged(qreal /*oldValue*/, qreal /*newValue*/);
+    void spatiumChanged(qreal /*oldValue*/, qreal /*newValue*/) override;
     void setLocalSpatium(double oldVal, double newVal, Fraction tick);
     bool genKeySig();
     bool showLedgerLines(const Fraction&) const;
 
-    QColor color() const { return _color; }
-    void setColor(const QColor& val) { _color = val; }
+    QColor color() const override { return _color; }
+    void setColor(const QColor& val) override { _color = val; }
     void undoSetColor(const QColor& val);
     void insertTime(const Fraction&, const Fraction& len);
 
diff --git a/libmscore/textbase.h b/libmscore/textbase.h
index 73fd1e92b733..aa3b8e128f1f 100644
--- a/libmscore/textbase.h
+++ b/libmscore/textbase.h
@@ -328,10 +328,10 @@ class TextBase : public Element
 
     virtual void write(XmlWriter& xml) const override;
     virtual void read(XmlReader&) override;
-    virtual void writeProperties(XmlWriter& xml) const { writeProperties(xml, true, true); }
+    virtual void writeProperties(XmlWriter& xml) const override { writeProperties(xml, true, true); }
     void writeProperties(XmlWriter& xml, bool writeText) const { writeProperties(xml, writeText, true); }
     void writeProperties(XmlWriter&, bool, bool) const;
-    bool readProperties(XmlReader&);
+    bool readProperties(XmlReader&) override;
 
     virtual void paste(EditData&);
 
@@ -373,8 +373,8 @@ class TextBase : public Element
     virtual QVariant propertyDefault(Pid id) const override;
     virtual void undoChangeProperty(Pid id, const QVariant& v, PropertyFlags ps) override;
     virtual Pid propertyId(const QStringRef& xmlName) const override;
-    virtual Sid getPropertyStyle(Pid) const;
-    virtual void styleChanged();
+    virtual Sid getPropertyStyle(Pid) const override;
+    virtual void styleChanged() override;
     void editInsertText(TextCursor*, const QString&);
 
     TextCursor* cursorFromEditData(const EditData&);
diff --git a/libmscore/textframe.h b/libmscore/textframe.h
index 25c2c5813305..2aaf90336961 100644
--- a/libmscore/textframe.h
+++ b/libmscore/textframe.h
@@ -37,8 +37,8 @@ class TBox : public VBox
     ScoreElement* treeChild(int idx) const override;
     int treeChildCount() const override;
 
-    virtual TBox* clone() const { return new TBox(*this); }
-    virtual ElementType type() const { return ElementType::TBOX; }
+    virtual TBox* clone() const override { return new TBox(*this); }
+    virtual ElementType type() const override { return ElementType::TBOX; }
     virtual void write(XmlWriter&) const override;
     using VBox::write;
     virtual void read(XmlReader&) override;
@@ -46,7 +46,7 @@ class TBox : public VBox
     virtual void add(Element* e) override;
     virtual void remove(Element* el) override;
 
-    virtual void layout();
+    virtual void layout() override;
     virtual QString accessibleExtraInfo() const override;
     Text* text() { return _text; }
 
diff --git a/libmscore/textlinebase.h b/libmscore/textlinebase.h
index f2d4ca932b91..e6a649ded33a 100644
--- a/libmscore/textlinebase.h
+++ b/libmscore/textlinebase.h
@@ -46,7 +46,7 @@ class TextLineBaseSegment : public LineSegment
     virtual void draw(QPainter*) const override;
 
     virtual void layout() override;
-    virtual void setSelected(bool f);
+    virtual void setSelected(bool f) override;
 
     virtual void spatiumChanged(qreal /*oldValue*/, qreal /*newValue*/) override;
 
diff --git a/libmscore/undo.h b/libmscore/undo.h
index 3c865d79f96f..5af68818488a 100644
--- a/libmscore/undo.h
+++ b/libmscore/undo.h
@@ -562,7 +562,7 @@ class AddElement : public UndoCommand
 public:
     AddElement(Element*);
     Element* getElement() const { return element; }
-    virtual void cleanup(bool);
+    virtual void cleanup(bool) override;
     virtual const char* name() const override;
 
     bool isFiltered(UndoCommand::Filter f, const Element* target) const override;
@@ -580,7 +580,7 @@ class RemoveElement : public UndoCommand
     RemoveElement(Element*);
     virtual void undo(EditData*) override;
     virtual void redo(EditData*) override;
-    virtual void cleanup(bool);
+    virtual void cleanup(bool) override;
     virtual const char* name() const override;
 
     bool isFiltered(UndoCommand::Filter f, const Element* target) const override;
diff --git a/mscore/editstaff.cpp b/mscore/editstaff.cpp
index 676dc264ebfd..697e514c95a8 100644
--- a/mscore/editstaff.cpp
+++ b/mscore/editstaff.cpp
@@ -394,7 +394,7 @@ void EditStaff::apply()
             if (instrumentFieldChanged) {
                 Segment* s = score->tick2segment(_tickStart, true, SegmentType::ChordRest);
                 const std::vector<Element*> elist = s ? s->findAnnotations(ElementType::INSTRUMENT_CHANGE,
-                                                                           part->startTrack(), part->endTrack()) : elist;
+                                                                           part->startTrack(), part->endTrack()) : std::vector<Element*>();
                 if (elist.size()) {
                     for (Element* e : elist) { // Change instrument in all Instrument Changes (for linked staves)
                         score->undo(new ChangeInstrument(toInstrumentChange(e), new Instrument(instrument)));
diff --git a/mscore/exportaudio.cpp b/mscore/exportaudio.cpp
index 7115df49b3b9..33e5a716e5c3 100644
--- a/mscore/exportaudio.cpp
+++ b/mscore/exportaudio.cpp
@@ -266,7 +266,7 @@ bool MuseScore::saveAudio(Score* score, const QString& name)
             return trueFrames * 2 * sizeof(float);
         }
 
-        bool open(QIODevice::OpenMode mode)
+        bool open(QIODevice::OpenMode mode) override
         {
             if ((mode& QIODevice::WriteOnly) == 0) {
                 return false;
@@ -286,7 +286,7 @@ bool MuseScore::saveAudio(Score* score, const QString& name)
             return QIODevice::open(mode);
         }
 
-        void close()
+        void close() override
         {
             if (sf && sf_close(sf)) {
                 qDebug("close soundfile failed");
diff --git a/mscore/metaedit.h b/mscore/metaedit.h
index 65e55005e33d..d4f3a7d39e4a 100644
--- a/mscore/metaedit.h
+++ b/mscore/metaedit.h
@@ -54,7 +54,7 @@ class MetaEditDialog : public QDialog, public Ui::MetaEditDialog
 
 public:
     MetaEditDialog(Score* score, QWidget* parent = nullptr);
-    virtual void accept();
+    virtual void accept() override;
 };
 } // namespace Ms
 #endif
diff --git a/mscore/musescore.h b/mscore/musescore.h
index b217d24075e0..3051d63220d2 100644
--- a/mscore/musescore.h
+++ b/mscore/musescore.h
@@ -411,11 +411,11 @@ class MuseScore : public QMainWindow, public MuseScoreCore, public mu::framework
 
     //---------------------
 
-    virtual void closeEvent(QCloseEvent*);
-    virtual void dragEnterEvent(QDragEnterEvent*);
-    virtual void dropEvent(QDropEvent*);
-    virtual void changeEvent(QEvent* e);
-    virtual void showEvent(QShowEvent* event);
+    virtual void closeEvent(QCloseEvent*) override;
+    virtual void dragEnterEvent(QDragEnterEvent*) override;
+    virtual void dropEvent(QDropEvent*) override;
+    virtual void changeEvent(QEvent* e) override;
+    virtual void showEvent(QShowEvent* event) override;
 
     void retranslate();
     void setMenuTitles();
@@ -458,7 +458,7 @@ class MuseScore : public QMainWindow, public MuseScoreCore, public mu::framework
     void showLayerManager();
     void updateUndoRedo();
     void changeScore(int);
-    virtual void resizeEvent(QResizeEvent*);
+    virtual void resizeEvent(QResizeEvent*) override;
     void showModeText(const QString& s, bool informScreenReader = true);
     void addRecentScore(const QString& scorePath);
 
@@ -549,7 +549,7 @@ private slots:
     QByteArray exportPdfAsJSON(Score*);
 
 public slots:
-    virtual void cmd(QAction* a);
+    virtual void cmd(QAction* a) override;
     void dirtyChanged(Score*);
     void setPos(const Fraction& tick);
     void pluginTriggered(int);
@@ -587,7 +587,7 @@ public slots:
     PlayPanel* getPlayPanel() const { return playPanel; }
     Mixer* getMixer() const { return mixer; }
     QMenu* genCreateMenu(QWidget* parent = 0);
-    virtual int appendScore(MasterScore*);
+    virtual int appendScore(MasterScore*) override;
     void midiCtrlReceived(int controller, int value);
     void showElementContext(Element* el);
     void cmdAppendMeasures(int);
@@ -643,7 +643,7 @@ public slots:
     bool restoreSession(bool);
     bool splitScreen() const { return _splitScreen; }
     void setSplitScreen(bool val);
-    virtual void setCurrentView(int tabIdx, int idx);
+    virtual void setCurrentView(int tabIdx, int idx) override;
     void loadPlugins();
     void unloadPlugins();
 #ifdef SCRIPT_INTERFACE
@@ -666,11 +666,11 @@ public slots:
     void loadFile(const QUrl&);
     QTemporaryFile* getTemporaryScoreFileCopy(const QFileInfo& info, const QString& baseNameTemplate);
     QNetworkAccessManager* networkManager();
-    virtual Score* openScore(const QString& fn, bool switchTab = true);
+    virtual Score* openScore(const QString& fn, bool switchTab = true) override;
     bool hasToCheckForUpdate();
     bool hasToCheckForExtensionsUpdate();
     static bool unstable();
-    bool eventFilter(QObject*, QEvent*);
+    bool eventFilter(QObject*, QEvent*) override;
     void setMidiRecordId(int id) { _midiRecordId = id; }
     int midiRecordId() const { return _midiRecordId; }
     void setDefaultPalette();
@@ -714,7 +714,7 @@ public slots:
     void printFile();
     void exportFile();
     bool exportParts();
-    virtual bool saveAs(Score*, bool saveCopy, const QString& path, const QString& ext);
+    virtual bool saveAs(Score*, bool saveCopy, const QString& path, const QString& ext) override;
     QString saveFilename(QString fn);
     bool savePdf(const QString& saveName);
     bool savePdf(Score* cs, const QString& saveName);
@@ -753,7 +753,7 @@ public slots:
 
     void scoreUnrolled(MasterScore* original);
 
-    virtual void closeScore(Score* score);
+    virtual void closeScore(Score* score) override;
 
     void addTempo();
     void addMetronome();
diff --git a/mscore/newwizard.h b/mscore/newwizard.h
index b0350460ca29..3dca82bb7ada 100644
--- a/mscore/newwizard.h
+++ b/mscore/newwizard.h
@@ -153,7 +153,7 @@ private slots:
     NewWizardTemplatePage(QWidget* parent = 0);
     virtual bool isComplete() const override;
     QString templatePath() const;
-    virtual void initializePage();
+    virtual void initializePage() override;
     void buildTemplatesList();
 };
 
diff --git a/mscore/pianoroll/pianoview.cpp b/mscore/pianoroll/pianoview.cpp
index 7cdfcad98d9d..97aeb2a0d1c9 100644
--- a/mscore/pianoroll/pianoview.cpp
+++ b/mscore/pianoroll/pianoview.cpp
@@ -904,8 +904,7 @@ QVector<Note*> PianoView::getSegmentNotes(Segment* seg, int track)
     ChordRest* cr = seg->cr(track);
     if (cr && cr->isChord()) {
         Chord* chord = toChord(cr);
-        // ToDo for Qt 5.15: QVector<Note*>::fromStdVector() vs. QVector<T>(vector.begin(), vector.end()) ??
-        notes.append(QVector<Note*>::fromStdVector(chord->notes()));
+        notes.append(QVector<Note*>(chord->notes().begin(), chord->notes().end()));
     }
 
     return notes;
diff --git a/mscore/playpanel.h b/mscore/playpanel.h
index 2424789a9a7c..d3dd1debc51b 100644
--- a/mscore/playpanel.h
+++ b/mscore/playpanel.h
@@ -40,10 +40,10 @@ class PlayPanel : public QDockWidget, private Ui::PlayPanelBase, public IPlayPan
     EnablePlayForWidget* enablePlay;
 
     Score* cs;
-    virtual void closeEvent(QCloseEvent*);
-    virtual void hideEvent(QHideEvent* event);
-    virtual void showEvent(QShowEvent*);
-    virtual bool eventFilter(QObject*, QEvent*);
+    virtual void closeEvent(QCloseEvent*) override;
+    virtual void hideEvent(QHideEvent* event) override;
+    virtual void showEvent(QShowEvent*) override;
+    virtual bool eventFilter(QObject*, QEvent*) override;
     virtual void keyPressEvent(QKeyEvent*) override;
     void updateTimeLabel(int sec);
     void updatePosLabel(int utick);
@@ -59,7 +59,7 @@ private slots:
     void volSpinBoxEdited();
 
 protected:
-    virtual void changeEvent(QEvent* event);
+    virtual void changeEvent(QEvent* event) override;
     void retranslate() { retranslateUi(this); }
 
 signals:
diff --git a/mscore/scoreBrowser.h b/mscore/scoreBrowser.h
index 917fe21d15f0..0bd22b242d30 100644
--- a/mscore/scoreBrowser.h
+++ b/mscore/scoreBrowser.h
@@ -41,7 +41,7 @@ class ScoreListWidget : public QListWidget
     QSize cellSize() const { return QSize(CELLW, CELLH); }
 
     // override so we pass wheel event to the parent scroll area
-    virtual void wheelEvent(QWheelEvent*) {}
+    virtual void wheelEvent(QWheelEvent*) override {}
 };
 
 //---------------------------------------------------------
diff --git a/mscore/scoretreeview.h b/mscore/scoretreeview.h
index b675e6001f95..71db06e24081 100644
--- a/mscore/scoretreeview.h
+++ b/mscore/scoretreeview.h
@@ -24,7 +24,7 @@ class ScoreTreeView : public QTreeView
     ScoreTreeView(QWidget* parent);
     ~ScoreTreeView();
 
-    void setModel(QAbstractItemModel* model);
+    void setModel(QAbstractItemModel* model) override;
     ScoreItemModel* model() const;
 
     void currentChanged(const QModelIndex& current, const QModelIndex& prev) override;
diff --git a/mscore/scoreview.h b/mscore/scoreview.h
index 9e49d0ca7ad6..e0af871861f8 100644
--- a/mscore/scoreview.h
+++ b/mscore/scoreview.h
@@ -207,7 +207,7 @@ class ScoreView : public QWidget, public MuseScoreView
 
     bool _blockShowEdit = false;
 
-    virtual void paintEvent(QPaintEvent*);
+    virtual void paintEvent(QPaintEvent*) override;
     void paint(const QRect&, QPainter&);
 
     void objectPopup(const QPoint&, Element*);
@@ -229,7 +229,7 @@ class ScoreView : public QWidget, public MuseScoreView
     virtual void mouseMoveEvent(QMouseEvent*) override;
     virtual void mousePressEvent(QMouseEvent*) override;
     virtual void mouseReleaseEvent(QMouseEvent*) override;
-    virtual void mouseDoubleClickEvent(QMouseEvent*);
+    virtual void mouseDoubleClickEvent(QMouseEvent*) override;
 
     virtual void keyPressEvent(QKeyEvent*) override;
     virtual void keyReleaseEvent(QKeyEvent*) override;
@@ -374,8 +374,8 @@ public slots:
     void setForeground(const QColor&);
 
     Page* addPage();
-    virtual void setScore(Score* s);
-    virtual void removeScore() { _score = 0; }
+    virtual void setScore(Score* s) override;
+    virtual void removeScore() override { _score = 0; }
 
     void setMag(qreal m);
     bool navigatorVisible() const;
@@ -409,7 +409,7 @@ public slots:
     bool hasEditGrips() const { return editData.element && editData.grips; }
     bool fotoMode() const;
 
-    virtual void setDropRectangle(const QRectF&);
+    virtual void setDropRectangle(const QRectF&) override;
     virtual void setDropTarget(const Element*) override;
     void setDropAnchorLines(const QVector<QLineF>& anchorList);
     const QTransform& matrix() const { return _matrix; }
@@ -440,7 +440,7 @@ public slots:
     void gotoMeasure(Measure*);
     void setFocusRect();
     void changeVoice(int voice);
-    virtual void drawBackground(QPainter* p, const QRectF& r) const;
+    virtual void drawBackground(QPainter* p, const QRectF& r) const override;
     bool fotoScoreViewDragTest(QMouseEvent*);
     bool fotoScoreViewDragRectTest(QMouseEvent*);
     void doDragFotoRect(QMouseEvent*);
@@ -449,7 +449,7 @@ public slots:
     void paintRect(bool printMode, QPainter& p, const QRectF& r, double mag);
     bool saveFotoAs(bool printMode, const QRectF&);
     void fotoDragDrop(QMouseEvent*);
-    void changeEditElement(Element*);
+    void changeEditElement(Element*) override;
 
     void cmdAppendMeasures(int, ElementType);
     void cmdInsertMeasures(int, ElementType);
@@ -466,12 +466,12 @@ public slots:
 
     SmoothPanSettings& panSettings() { return _panSettings; }
 
-    virtual void layoutChanged();
-    virtual void dataChanged(const QRectF&);
-    virtual void updateAll() { update(); }
+    virtual void layoutChanged() override;
+    virtual void dataChanged(const QRectF&) override;
+    virtual void updateAll() override { update(); }
     virtual void adjustCanvasPosition(const Element* el, bool playBack, int staff = -1) override;
-    virtual void setCursor(const QCursor& c) { QWidget::setCursor(c); }
-    virtual QCursor cursor() const { return QWidget::cursor(); }
+    virtual void setCursor(const QCursor& c) override { QWidget::setCursor(c); }
+    virtual QCursor cursor() const override { return QWidget::cursor(); }
     void loopUpdate(bool val) { loopToggled(val); }
 
     void moveViewportToLastEdit();
@@ -484,7 +484,7 @@ public slots:
     Element* getEditElement();
     void onElementDestruction(Element*) override;
 
-    virtual Element* elementNear(QPointF);
+    virtual Element* elementNear(QPointF) override;
     QList<Element*> elementsNear(QPointF);
     void editArticulationProperties(Articulation*);
     void editTimeSigProperties(TimeSig*);
diff --git a/mscore/seq.h b/mscore/seq.h
index 43cfebce9abd..d1e079fd5731 100644
--- a/mscore/seq.h
+++ b/mscore/seq.h
@@ -267,7 +267,7 @@ public slots:
     void sendMessage(SeqMsg&) const;
 
     void setController(int, int, int);
-    virtual void sendEvent(const NPlayEvent&);
+    virtual void sendEvent(const NPlayEvent&) override;
     void setScoreView(ScoreView*);
     MasterScore* score() const { return cs; }
     ScoreView* viewer() const { return cv; }
diff --git a/mscore/startcenter.h b/mscore/startcenter.h
index 06ad0896616e..a9c5ce6ea21e 100644
--- a/mscore/startcenter.h
+++ b/mscore/startcenter.h
@@ -78,7 +78,7 @@ class Startcenter : public AbstractDialog, public Ui::Startcenter
 #ifdef USE_WEBENGINE
     MyWebView* _webView;
 #endif
-    virtual void closeEvent(QCloseEvent*);
+    virtual void closeEvent(QCloseEvent*) override;
 
 private slots:
     void loadScore(QString);
@@ -86,7 +86,7 @@ private slots:
     void openScoreClicked();
 
 protected:
-    virtual void retranslate() { retranslateUi(this); }
+    virtual void retranslate() override { retranslateUi(this); }
 
 signals:
     void closed(bool);
diff --git a/mscore/synthcontrol.h b/mscore/synthcontrol.h
index 4d4739db1c44..7648a4ecdc96 100644
--- a/mscore/synthcontrol.h
+++ b/mscore/synthcontrol.h
@@ -38,9 +38,9 @@ class SynthControl : public QWidget, Ui::SynthControl
     EnablePlayForWidget* enablePlay;
     bool _dirty    { false };
 
-    virtual void closeEvent(QCloseEvent*);
-    virtual void showEvent(QShowEvent*);
-    virtual bool eventFilter(QObject*, QEvent*);
+    virtual void closeEvent(QCloseEvent*) override;
+    virtual void showEvent(QShowEvent*) override;
+    virtual bool eventFilter(QObject*, QEvent*) override;
     virtual void keyPressEvent(QKeyEvent*) override;
     void updateGui();
     void readSettings();
@@ -70,7 +70,7 @@ private slots:
     void closed(bool);
 
 protected:
-    virtual void changeEvent(QEvent* event);
+    virtual void changeEvent(QEvent* event) override;
     void retranslate() { retranslateUi(this); }
 
 public slots:
diff --git a/mscore/timeline.h b/mscore/timeline.h
index 2ad493156cce..ff0d4f823673 100644
--- a/mscore/timeline.h
+++ b/mscore/timeline.h
@@ -84,12 +84,12 @@ class TRowLabels : public QGraphicsView
     std::map<MouseOverValue, QPixmap*> _mouseoverMap;
     std::tuple<QGraphicsPixmapItem*, MouseOverValue, unsigned> _oldItemInfo;
 
-    virtual void resizeEvent(QResizeEvent*);
-    virtual void mousePressEvent(QMouseEvent* event);
-    virtual void mouseMoveEvent(QMouseEvent* event);
-    virtual void mouseReleaseEvent(QMouseEvent* event);
+    virtual void resizeEvent(QResizeEvent*) override;
+    virtual void mousePressEvent(QMouseEvent* event) override;
+    virtual void mouseMoveEvent(QMouseEvent* event) override;
+    virtual void mouseReleaseEvent(QMouseEvent* event) override;
     virtual void contextMenuEvent(QContextMenuEvent*) override;
-    virtual void leaveEvent(QEvent*);
+    virtual void leaveEvent(QEvent*) override;
 
 private slots:
     void restrictScroll(int value);
@@ -178,11 +178,11 @@ class Timeline : public QGraphicsView
     bool _metaValue = false;
     ViewState state = ViewState::NORMAL;
 
-    virtual void mousePressEvent(QMouseEvent* event);
-    virtual void mouseMoveEvent(QMouseEvent* event);
-    virtual void mouseReleaseEvent(QMouseEvent*);
-    virtual void wheelEvent(QWheelEvent* event);
-    virtual void leaveEvent(QEvent*);
+    virtual void mousePressEvent(QMouseEvent* event) override;
+    virtual void mouseMoveEvent(QMouseEvent* event) override;
+    virtual void mouseReleaseEvent(QMouseEvent*) override;
+    virtual void wheelEvent(QWheelEvent* event) override;
+    virtual void leaveEvent(QEvent*) override;
 
     unsigned correctMetaRow(unsigned row);
     int correctStave(int stave);
diff --git a/mscore/widgets/filterabletreeview.h b/mscore/widgets/filterabletreeview.h
index 8f2d831ffb94..8f5a8b4572f6 100644
--- a/mscore/widgets/filterabletreeview.h
+++ b/mscore/widgets/filterabletreeview.h
@@ -58,7 +58,7 @@ class FilterableTreeViewTemplate : public T, public FilterableView
         toInitialState(FilterableTreeViewTemplate<T>::rootIndex());
     }
 
-    virtual void toInitialState(const QModelIndex& node);
+    virtual void toInitialState(const QModelIndex& node) override;
     inline virtual bool filter(const QString& searchString) override
     {
         return filter(searchString, FilterableTreeViewTemplate<T>::rootIndex());
diff --git a/mu4/appshell/appshellmodule.h b/mu4/appshell/appshellmodule.h
index cb037248c19d..3263ec7a64b8 100644
--- a/mu4/appshell/appshellmodule.h
+++ b/mu4/appshell/appshellmodule.h
@@ -29,7 +29,7 @@ class AppShellModule : public framework::IModuleSetup
 public:
     AppShellModule();
 
-    std::string moduleName() const;
+    std::string moduleName() const override;
 
     void resolveImports() override;
 
diff --git a/mu4/appshell/qml/DevTools/Audio/SynthSettings.qml b/mu4/appshell/qml/DevTools/Audio/SynthSettings.qml
index 99c31b64c605..6f7ddf8111fc 100644
--- a/mu4/appshell/qml/DevTools/Audio/SynthSettings.qml
+++ b/mu4/appshell/qml/DevTools/Audio/SynthSettings.qml
@@ -98,14 +98,14 @@ Rectangle {
 
             Connections {
                 target: settingsModel
-                onSelectedChanged: {
+                function onSelectedChanged(name) {
                     if (name === "Zerberus") {
                         zerberusPanel.selectedSoundFonts = []
                         zerberusPanel.selectedSoundFonts = settingsModel.selectedSoundFonts("Zerberus")
                     }
                 }
 
-                onAvalaibleChanged: {
+                function onAvalaibleChanged(name) {
                     if (name === "Zerberus") {
                         zerberusPanel.avalaibleSoundFonts = []
                         zerberusPanel.avalaibleSoundFonts = settingsModel.avalaibleSoundFonts("Zerberus")
diff --git a/mu4/appshell/qml/Settings/SettingsPage.qml b/mu4/appshell/qml/Settings/SettingsPage.qml
index 30b3d6286be0..2d37430999ec 100644
--- a/mu4/appshell/qml/Settings/SettingsPage.qml
+++ b/mu4/appshell/qml/Settings/SettingsPage.qml
@@ -84,7 +84,9 @@ DockPage {
 
                         Connections {
                             target: loader.item
-                            onChanged: settingsModel.changeVal(model.index, newVal)
+                            function onChanged(newVal) {
+                                settingsModel.changeVal(model.index, newVal)
+                            }
                         }
                     }
                 }
diff --git a/mu4/commonscene/exampleview.h b/mu4/commonscene/exampleview.h
index cf86e72b3cc0..a85a6bcba64b 100644
--- a/mu4/commonscene/exampleview.h
+++ b/mu4/commonscene/exampleview.h
@@ -50,17 +50,17 @@ class ExampleView : public QFrame, public MuseScoreView
     QPointF startMove;
 
     void drawElements(QPainter& painter, const QList<Element*>& el);
-    void setDropTarget(const Element* el);
-
-    virtual void paintEvent(QPaintEvent*);
-    virtual void dragEnterEvent(QDragEnterEvent*);
-    virtual void dragLeaveEvent(QDragLeaveEvent*);
-    virtual void dragMoveEvent(QDragMoveEvent*);
-    virtual void wheelEvent(QWheelEvent*);
-    virtual void dropEvent(QDropEvent*);
-    virtual void mousePressEvent(QMouseEvent*);
+    void setDropTarget(const Element* el) override;
+
+    virtual void paintEvent(QPaintEvent*) override;
+    virtual void dragEnterEvent(QDragEnterEvent*) override;
+    virtual void dragLeaveEvent(QDragLeaveEvent*) override;
+    virtual void dragMoveEvent(QDragMoveEvent*) override;
+    virtual void wheelEvent(QWheelEvent*) override;
+    virtual void dropEvent(QDropEvent*) override;
+    virtual void mousePressEvent(QMouseEvent*) override;
     void constraintCanvas(int* dxx);
-    virtual QSize sizeHint() const;
+    virtual QSize sizeHint() const override;
 
 signals:
     void noteClicked(Note*);
@@ -70,20 +70,20 @@ class ExampleView : public QFrame, public MuseScoreView
     ExampleView(QWidget* parent = 0);
     ~ExampleView();
     void resetMatrix();
-    virtual void layoutChanged();
-    virtual void dataChanged(const QRectF&);
-    virtual void updateAll();
-    virtual void adjustCanvasPosition(const Element* el, bool playBack, int staff = -1);
-    virtual void setScore(Score*);
-    virtual void removeScore();
-
-    virtual void changeEditElement(Element*);
-    virtual QCursor cursor() const;
-    virtual void setCursor(const QCursor&);
-    virtual void setDropRectangle(const QRectF&);
+    virtual void layoutChanged() override;
+    virtual void dataChanged(const QRectF&) override;
+    virtual void updateAll() override;
+    virtual void adjustCanvasPosition(const Element* el, bool playBack, int staff = -1) override;
+    virtual void setScore(Score*) override;
+    virtual void removeScore() override;
+
+    virtual void changeEditElement(Element*) override;
+    virtual QCursor cursor() const override;
+    virtual void setCursor(const QCursor&) override;
+    virtual void setDropRectangle(const QRectF&) override;
     virtual void cmdAddSlur(Note* firstNote, Note* lastNote);
-    virtual Element* elementNear(QPointF);
-    virtual void drawBackground(QPainter*, const QRectF&) const;
+    virtual Element* elementNear(QPointF) override;
+    virtual void drawBackground(QPainter*, const QRectF&) const override;
     void dragExampleView(QMouseEvent* ev);
     virtual const QRect geometry() const override { return QFrame::geometry(); }
 };
diff --git a/mu4/context/internal/globalcontext.h b/mu4/context/internal/globalcontext.h
index 7062ce1e3998..3e19b77fe2ee 100644
--- a/mu4/context/internal/globalcontext.h
+++ b/mu4/context/internal/globalcontext.h
@@ -48,7 +48,7 @@ class GlobalContext : public IGlobalContext, public shortcuts::IShortcutContextR
     notation::INotationPtr currentNotation() const override;
     async::Notification currentNotationChanged() const override;
 
-    shortcuts::ShortcutContext currentShortcutContext() const;
+    shortcuts::ShortcutContext currentShortcutContext() const override;
 
 private:
     std::vector<notation::IMasterNotationPtr> m_masterNotations;
diff --git a/mu4/inspector/models/general/appearance/appearancesettingsmodel.cpp b/mu4/inspector/models/general/appearance/appearancesettingsmodel.cpp
index fd275dd7d5ca..a348b20f07b7 100644
--- a/mu4/inspector/models/general/appearance/appearancesettingsmodel.cpp
+++ b/mu4/inspector/models/general/appearance/appearancesettingsmodel.cpp
@@ -47,11 +47,11 @@ void AppearanceSettingsModel::loadProperties()
     loadPropertyItem(m_color);
     loadPropertyItem(m_arrangeOrder);
 
-    loadPropertyItem(m_horizontalOffset, [this](const QVariant& elementPropertyValue) -> QVariant {
+    loadPropertyItem(m_horizontalOffset, [](const QVariant& elementPropertyValue) -> QVariant {
         return DataFormatter::formatDouble(elementPropertyValue.toPointF().x());
     });
 
-    loadPropertyItem(m_verticalOffset, [this](const QVariant& elementPropertyValue) -> QVariant {
+    loadPropertyItem(m_verticalOffset, [](const QVariant& elementPropertyValue) -> QVariant {
         return DataFormatter::formatDouble(elementPropertyValue.toPointF().y());
     });
 }
diff --git a/mu4/inspector/models/inspectorlistmodel.cpp b/mu4/inspector/models/inspectorlistmodel.cpp
index 39f268b2357e..3b966fc395c2 100644
--- a/mu4/inspector/models/inspectorlistmodel.cpp
+++ b/mu4/inspector/models/inspectorlistmodel.cpp
@@ -141,13 +141,11 @@ void InspectorListModel::removeUnusedModels(const QSet<Ms::ElementType>& newElem
             continue;
         }
 
-        // ToDo for Qt 5.15: QList<Ms::ElementType>::toSet vs. QSet<T>(list.begin(), list.end()) ??
-        QSet<Ms::ElementType> supportedElementTypes
-            = AbstractInspectorModel::supportedElementTypesBySectionType(model->sectionType()).toSet();
+        auto supportedElementTypes = AbstractInspectorModel::supportedElementTypesBySectionType(model->sectionType());
+        QSet<Ms::ElementType> supportedElementTypesSet(supportedElementTypes.begin(), supportedElementTypes.end());
+        supportedElementTypesSet.intersect(newElementTypeSet);
 
-        supportedElementTypes.intersect(newElementTypeSet);
-
-        if (supportedElementTypes.isEmpty()) {
+        if (supportedElementTypesSet.isEmpty()) {
             modelsToRemove << model;
         }
     }
@@ -214,10 +212,13 @@ void InspectorListModel::subscribeOnSelectionChanges()
         }
 
         m_notation->interaction()->selectionChanged().onNotify(this, [this]() {
-            // ToDo for Qt 5.15: QVector<Note*>::fromStdVector() vs. QVector<T>(vector.begin(), vector.end()) ??
-            QVector<Ms::Element*> elements = QVector<Ms::Element*>::fromStdVector(m_notation->interaction()->selection()->elements());
+            QList<Ms::Element*> elements;
+
+            for (Ms::Element* element: m_notation->interaction()->selection()->elements()) {
+                elements << element;
+            }
 
-            setElementList(QList<Ms::Element*>::fromVector(elements));
+            setElementList(elements);
         });
     });
 #endif
diff --git a/mu4/inspector/models/notation/notes/beams/internal/beammodesmodel.cpp b/mu4/inspector/models/notation/notes/beams/internal/beammodesmodel.cpp
index 77227811fe6e..e38de3527f53 100644
--- a/mu4/inspector/models/notation/notes/beams/internal/beammodesmodel.cpp
+++ b/mu4/inspector/models/notation/notes/beams/internal/beammodesmodel.cpp
@@ -23,7 +23,7 @@ void BeamModesModel::loadProperties()
 {
     loadPropertyItem(m_mode);
 
-    loadPropertyItem(m_isFeatheringAvailable, [this](const QVariant& elementPropertyValue) -> QVariant {
+    loadPropertyItem(m_isFeatheringAvailable, [](const QVariant& elementPropertyValue) -> QVariant {
         Ms::TDuration durationType = elementPropertyValue.value<Ms::TDuration>();
 
         switch (durationType.type()) {
diff --git a/mu4/inspector/models/notation/notes/hooks/hooksettingsmodel.cpp b/mu4/inspector/models/notation/notes/hooks/hooksettingsmodel.cpp
index 51a0dc85f861..ee65f3e7cff7 100644
--- a/mu4/inspector/models/notation/notes/hooks/hooksettingsmodel.cpp
+++ b/mu4/inspector/models/notation/notes/hooks/hooksettingsmodel.cpp
@@ -29,11 +29,11 @@ void HookSettingsModel::requestElements()
 
 void HookSettingsModel::loadProperties()
 {
-    loadPropertyItem(m_horizontalOffset, [this](const QVariant& elementPropertyValue) -> QVariant {
+    loadPropertyItem(m_horizontalOffset, [](const QVariant& elementPropertyValue) -> QVariant {
         return DataFormatter::formatDouble(elementPropertyValue.toPointF().x());
     });
 
-    loadPropertyItem(m_verticalOffset, [this](const QVariant& elementPropertyValue) -> QVariant {
+    loadPropertyItem(m_verticalOffset, [](const QVariant& elementPropertyValue) -> QVariant {
         return DataFormatter::formatDouble(elementPropertyValue.toPointF().y());
     });
 }
diff --git a/mu4/inspector/models/notation/notes/noteheads/noteheadsettingsmodel.cpp b/mu4/inspector/models/notation/notes/noteheads/noteheadsettingsmodel.cpp
index c760777b31d8..3881367165c7 100644
--- a/mu4/inspector/models/notation/notes/noteheads/noteheadsettingsmodel.cpp
+++ b/mu4/inspector/models/notation/notes/noteheads/noteheadsettingsmodel.cpp
@@ -41,7 +41,7 @@ void NoteheadSettingsModel::requestElements()
 
 void NoteheadSettingsModel::loadProperties()
 {
-    loadPropertyItem(m_isHeadHidden, [this](const QVariant& isVisible) -> QVariant {
+    loadPropertyItem(m_isHeadHidden, [](const QVariant& isVisible) -> QVariant {
         return !isVisible.toBool();
     });
 
@@ -50,11 +50,11 @@ void NoteheadSettingsModel::loadProperties()
     loadPropertyItem(m_headType);
     loadPropertyItem(m_dotPosition);
 
-    loadPropertyItem(m_horizontalOffset, [this](const QVariant& elementPropertyValue) -> QVariant {
+    loadPropertyItem(m_horizontalOffset, [](const QVariant& elementPropertyValue) -> QVariant {
         return DataFormatter::formatDouble(elementPropertyValue.toPointF().x());
     });
 
-    loadPropertyItem(m_verticalOffset, [this](const QVariant& elementPropertyValue) -> QVariant {
+    loadPropertyItem(m_verticalOffset, [](const QVariant& elementPropertyValue) -> QVariant {
         return DataFormatter::formatDouble(elementPropertyValue.toPointF().y());
     });
 }
diff --git a/mu4/inspector/models/notation/tempos/temposettingsmodel.cpp b/mu4/inspector/models/notation/tempos/temposettingsmodel.cpp
index c19d4625ef0d..ceca7e83ab0d 100644
--- a/mu4/inspector/models/notation/tempos/temposettingsmodel.cpp
+++ b/mu4/inspector/models/notation/tempos/temposettingsmodel.cpp
@@ -29,7 +29,7 @@ void TempoSettingsModel::requestElements()
 void TempoSettingsModel::loadProperties()
 {
     loadPropertyItem(m_isDefaultTempoForced);
-    loadPropertyItem(m_tempo, [this](const QVariant& elementPropertyValue) -> QVariant {
+    loadPropertyItem(m_tempo, [](const QVariant& elementPropertyValue) -> QVariant {
         return DataFormatter::formatDouble(elementPropertyValue.toDouble());
     });
 }
diff --git a/mu4/instruments/internal/instrumentsreader.cpp b/mu4/instruments/internal/instrumentsreader.cpp
index 99a152b01d2a..7121484d6cd8 100644
--- a/mu4/instruments/internal/instrumentsreader.cpp
+++ b/mu4/instruments/internal/instrumentsreader.cpp
@@ -52,7 +52,10 @@ RetVal<InstrumentsMeta> InstrumentsReader::readMeta(const io::path& path) const
                 || reader.name() == "InstrumentGroup") {
                 GroupMeta groupMeta = readGroupMeta(reader, meta);
                 meta.groups.insert(groupMeta.group.id, groupMeta.group);
-                meta.instrumentTemplates.unite(groupMeta.templates);
+
+                for (auto it = groupMeta.templates.cbegin(); it != groupMeta.templates.cend(); ++it) {
+                    meta.instrumentTemplates.insert(it.key(), it.value());
+                }
             } else if (reader.name() == "Articulation") {
                 MidiArticulation articulation = readArticulation(reader);
                 meta.articulations.insert(articulation.name, articulation); // TODO: name?
diff --git a/mu4/instruments/internal/instrumentsrepository.cpp b/mu4/instruments/internal/instrumentsrepository.cpp
index 70603092dacc..8a3314d11a7b 100644
--- a/mu4/instruments/internal/instrumentsrepository.cpp
+++ b/mu4/instruments/internal/instrumentsrepository.cpp
@@ -78,10 +78,25 @@ void InstrumentsRepository::load()
             continue;
         }
 
-        m_instrumentsMeta.instrumentTemplates.unite(metaInstrument.val.instrumentTemplates);
-        m_instrumentsMeta.articulations.unite(metaInstrument.val.articulations);
-        m_instrumentsMeta.genres.unite(metaInstrument.val.genres);
-        m_instrumentsMeta.groups.unite(metaInstrument.val.groups);
+        const InstrumentTemplateHash& templates = metaInstrument.val.instrumentTemplates;
+        for (auto it = templates.cbegin(); it != templates.cend(); ++it) {
+            m_instrumentsMeta.instrumentTemplates.insert(it.key(), it.value());
+        }
+
+        const MidiArticulationHash& acticulations = metaInstrument.val.articulations;
+        for (auto it = acticulations.cbegin(); it != acticulations.cend(); ++it) {
+            m_instrumentsMeta.articulations.insert(it.key(), it.value());
+        }
+
+        const InstrumentGenreHash& genres = metaInstrument.val.genres;
+        for (auto it = genres.cbegin(); it != genres.cend(); ++it) {
+            m_instrumentsMeta.genres.insert(it.key(), it.value());
+        }
+
+        const InstrumentGroupHash& groups = metaInstrument.val.groups;
+        for (auto it = groups.cbegin(); it != groups.cend(); ++it) {
+            m_instrumentsMeta.groups.insert(it.key(), it.value());
+        }
     }
 
     for (InstrumentTemplate& instrumentTemplate: m_instrumentsMeta.instrumentTemplates) {
diff --git a/mu4/instruments/qml/MuseScore/Instruments/ChooseInstrumentsPage.qml b/mu4/instruments/qml/MuseScore/Instruments/ChooseInstrumentsPage.qml
index 48a42b91eeee..7b2251ddb7de 100644
--- a/mu4/instruments/qml/MuseScore/Instruments/ChooseInstrumentsPage.qml
+++ b/mu4/instruments/qml/MuseScore/Instruments/ChooseInstrumentsPage.qml
@@ -50,7 +50,7 @@ Rectangle {
             Connections {
                 target: instrumentsModel
 
-                onSelectedFamilyChanged: {
+                function onSelectedFamilyChanged(family) {
                     familyView.setFamily(family)
                 }
             }
@@ -111,7 +111,7 @@ Rectangle {
 
         Column {
             Layout.preferredWidth: 30
-            anchors.verticalCenter: parent.verticalCenter
+            Layout.alignment: Qt.AlignVCenter
 
             spacing: 12
 
diff --git a/mu4/instruments/qml/MuseScore/Instruments/InstrumentsView.qml b/mu4/instruments/qml/MuseScore/Instruments/InstrumentsView.qml
index 0afbc9185ec3..62aa67fe9100 100644
--- a/mu4/instruments/qml/MuseScore/Instruments/InstrumentsView.qml
+++ b/mu4/instruments/qml/MuseScore/Instruments/InstrumentsView.qml
@@ -159,7 +159,7 @@ Item {
 
             Connections {
                 target: privateProperties
-                onCurrentInstrumentIndexChanged: {
+                function onCurrentInstrumentIndexChanged() {
                     if (privateProperties.currentInstrumentIndex == index) {
                         item.resetCurrentInstrument()
                     }
diff --git a/mu4/instruments/view/instrumentlistmodel.cpp b/mu4/instruments/view/instrumentlistmodel.cpp
index 25badd3c2aba..39604cfb28af 100644
--- a/mu4/instruments/view/instrumentlistmodel.cpp
+++ b/mu4/instruments/view/instrumentlistmodel.cpp
@@ -204,7 +204,7 @@ void InstrumentListModel::unselectInstrument(const QString& id)
 
 void InstrumentListModel::swapSelectedInstruments(int firstIndex, int secondIndex)
 {
-    m_selectedInstruments.swap(firstIndex, secondIndex);
+    m_selectedInstruments.swapItemsAt(firstIndex, secondIndex);
     emit selectedInstrumentsChanged();
 }
 
diff --git a/mu4/languages/qml/MuseScore/Languages/LanguagesPage.qml b/mu4/languages/qml/MuseScore/Languages/LanguagesPage.qml
index bfb6d75c7ddf..04e4dd5074c7 100644
--- a/mu4/languages/qml/MuseScore/Languages/LanguagesPage.qml
+++ b/mu4/languages/qml/MuseScore/Languages/LanguagesPage.qml
@@ -176,10 +176,10 @@ Item {
 
             Connections {
                 target: languageListModel
-                onProgress: {
+                function onProgress(status, indeterminate, current, total) {
                     languageInfo.setProgress(status, indeterminate, current, total)
                 }
-                onFinish: {
+                function onFinish() {
                     languageInfo.resetProgress()
                 }
             }
diff --git a/mu4/notation/internal/notationinteraction.cpp b/mu4/notation/internal/notationinteraction.cpp
index 44e652344d70..5057a902e34f 100644
--- a/mu4/notation/internal/notationinteraction.cpp
+++ b/mu4/notation/internal/notationinteraction.cpp
@@ -652,7 +652,7 @@ void NotationInteraction::drag(const QPointF& fromPos, const QPointF& toPos, Dra
         }
     }
 
-    setAnchorLines(anchorLines.toStdVector());
+    setAnchorLines(std::vector<QLineF>(anchorLines.begin(), anchorLines.end()));
 
     m_dragChanged.notify();
 
diff --git a/mu4/notation/notationmodule.h b/mu4/notation/notationmodule.h
index 120ac566a247..cab622e70cfa 100644
--- a/mu4/notation/notationmodule.h
+++ b/mu4/notation/notationmodule.h
@@ -27,7 +27,7 @@ class NotationModule : public framework::IModuleSetup
 {
 public:
 
-    std::string moduleName() const;
+    std::string moduleName() const override;
 
     void registerExports() override;
     void resolveImports() override;
diff --git a/mu4/notation/view/notationpaintview.cpp b/mu4/notation/view/notationpaintview.cpp
index d85d0d6557e8..278ee09a44e3 100644
--- a/mu4/notation/view/notationpaintview.cpp
+++ b/mu4/notation/view/notationpaintview.cpp
@@ -28,8 +28,6 @@
 using namespace mu::notation;
 using namespace mu::notation;
 
-static constexpr int PREF_UI_CANVAS_MISC_SELECTIONPROXIMITY = 6;
-
 NotationPaintView::NotationPaintView()
     : QQuickPaintedItem()
 {
@@ -75,7 +73,7 @@ NotationPaintView::NotationPaintView()
     });
 
     // test
-    dispatcher()->reg(this, "copy", [this](const actions::ActionName&) {
+    dispatcher()->reg(this, "copy", [](const actions::ActionName&) {
         LOGI() << "NotationPaintView copy";
     });
 }
diff --git a/mu4/notation/view/notationpaintview.h b/mu4/notation/view/notationpaintview.h
index 4264d82db708..b3e4e818a742 100644
--- a/mu4/notation/view/notationpaintview.h
+++ b/mu4/notation/view/notationpaintview.h
@@ -64,7 +64,7 @@ class NotationPaintView : public QQuickPaintedItem, public IControlledView, publ
     void setZoom(int zoomPercentage, const QPoint& pos) override;
 
     bool isNoteEnterMode() const override;
-    void showShadowNote(const QPointF& pos);
+    void showShadowNote(const QPointF& pos) override;
 
     notation::INotationInteraction* notationInteraction() const override;
     notation::INotationPlayback* notationPlayback() const override;
diff --git a/mu4/notation/view/notationviewinputcontroller.cpp b/mu4/notation/view/notationviewinputcontroller.cpp
index 17944889df72..07820c1fbba4 100644
--- a/mu4/notation/view/notationviewinputcontroller.cpp
+++ b/mu4/notation/view/notationviewinputcontroller.cpp
@@ -111,7 +111,7 @@ void NotationViewInputController::wheelEvent(QWheelEvent* ev)
     // Windows touch pad pinches also execute this
     if (keyState & Qt::ControlModifier) {
         int zoom = configuration()->currentZoom().val * qPow(1.1, steps);
-        QPoint pos = m_view->toLogical(ev->pos());
+        QPoint pos = m_view->toLogical(ev->position().toPoint());
         setZoom(zoom, pos);
     } else if (keyState & Qt::ShiftModifier) {
         m_view->scrollHorizontal(dy);
diff --git a/mu4/palette/internal/palette/palette.cpp b/mu4/palette/internal/palette/palette.cpp
index 893294fe1730..746ed774a42d 100644
--- a/mu4/palette/internal/palette/palette.cpp
+++ b/mu4/palette/internal/palette/palette.cpp
@@ -123,7 +123,7 @@ Palette::Palette(std::unique_ptr<PalettePanel> pp, QWidget* parent)
     }
 
     if (moreElements()) {
-        connect(this, &Palette::displayMore, [this](const QString& arg) {
+        connect(this, &Palette::displayMore, [](const QString& arg) {
                 adapter()->showMasterPalette(arg);
             });
     }
diff --git a/mu4/palette/internal/palette/palette.h b/mu4/palette/internal/palette/palette.h
index 2668ec172f57..bb9549beb359 100644
--- a/mu4/palette/internal/palette/palette.h
+++ b/mu4/palette/internal/palette/palette.h
@@ -59,7 +59,7 @@ class PaletteScrollArea : public QScrollArea
     Q_OBJECT
     bool _restrictHeight;
 
-    virtual void resizeEvent(QResizeEvent*);
+    virtual void resizeEvent(QResizeEvent*) override;
 
 protected:
     virtual void keyPressEvent(QKeyEvent* event) override;
@@ -199,8 +199,8 @@ private slots:
     void setCurrentIdx(int i) { currentIdx = i; }
     bool isFilterActive() { return filterActive == true; }
     QList<PaletteCell*> getDragCells() { return dragCells; }
-    virtual int heightForWidth(int) const;
-    virtual QSize sizeHint() const;
+    virtual int heightForWidth(int) const override;
+    virtual QSize sizeHint() const override;
     int idx(const QPoint&) const;
 };
 } // namespace Ms
diff --git a/mu4/palette/internal/palette/palettemodel.h b/mu4/palette/internal/palette/palettemodel.h
index 37a1b07eb935..f65b4826589c 100644
--- a/mu4/palette/internal/palette/palettemodel.h
+++ b/mu4/palette/internal/palette/palettemodel.h
@@ -166,8 +166,8 @@ public slots:
     QMimeData* mimeData(const QModelIndexList& indexes) const override;
     QStringList mimeTypes() const override;
 
-    bool canDropMimeData(const QMimeData* data, Qt::DropAction action, int row, int column,const QModelIndex& parent) const;
-    bool dropMimeData(const QMimeData* data, Qt::DropAction action, int row, int column, const QModelIndex& parent);
+    bool canDropMimeData(const QMimeData* data, Qt::DropAction action, int row, int column,const QModelIndex& parent) const override;
+    bool dropMimeData(const QMimeData* data, Qt::DropAction action, int row, int column, const QModelIndex& parent) override;
 
     QModelIndexList match(const QModelIndex& start, int role, const QVariant& value, int hits,Qt::MatchFlags flags) const override;
     QModelIndex findPaletteCell(const PaletteCell& cell, const QModelIndex& parent) const;
diff --git a/mu4/palette/internal/workspacepalettestream.cpp b/mu4/palette/internal/workspacepalettestream.cpp
index b4a154bfc749..53f0837d94d2 100644
--- a/mu4/palette/internal/workspacepalettestream.cpp
+++ b/mu4/palette/internal/workspacepalettestream.cpp
@@ -26,7 +26,7 @@ using namespace mu::workspace;
 std::shared_ptr<AbstractData> WorkspacePaletteStream::read(Ms::XmlReader& xml) const
 {
     std::shared_ptr<PaletteWorkspaceData> data = std::make_shared<PaletteWorkspaceData>();
-    data->tree = std::move(std::unique_ptr<Ms::PaletteTree>(new Ms::PaletteTree));
+    data->tree = std::unique_ptr<Ms::PaletteTree>(new Ms::PaletteTree);
     data->tree->read(xml);
     return data;
 }
diff --git a/mu4/plugins/view/pluginsmodel.cpp b/mu4/plugins/view/pluginsmodel.cpp
index 7d006420835f..2a79a772c583 100644
--- a/mu4/plugins/view/pluginsmodel.cpp
+++ b/mu4/plugins/view/pluginsmodel.cpp
@@ -176,7 +176,7 @@ QStringList PluginsModel::categories() const
         result << plugin.category;
     }
 
-    return result.toList();
+    return result.values();
 }
 
 void PluginsModel::updatePlugin(const PluginInfo& plugin)
diff --git a/mu4/userscores/qml/MuseScore/UserScores/NewScoreDialog.qml b/mu4/userscores/qml/MuseScore/UserScores/NewScoreDialog.qml
index 2a829d5b0620..56daa49ce940 100644
--- a/mu4/userscores/qml/MuseScore/UserScores/NewScoreDialog.qml
+++ b/mu4/userscores/qml/MuseScore/UserScores/NewScoreDialog.qml
@@ -34,14 +34,10 @@ QmlDialog {
 
             ChooseInstrumentsAndTemplatesPage {
                 id: instrumentsAndTemplatePage
-
-                anchors.fill: parent
             }
 
             ScoreInfoPage {
                 id: scoreInfoPage
-
-                anchors.fill: parent
             }
         }
 
diff --git a/mu4/userscores/qml/MuseScore/UserScores/internal/ChooseInstrumentsAndTemplatesPage.qml b/mu4/userscores/qml/MuseScore/UserScores/internal/ChooseInstrumentsAndTemplatesPage.qml
index dcefd9717604..1990a2c388e2 100644
--- a/mu4/userscores/qml/MuseScore/UserScores/internal/ChooseInstrumentsAndTemplatesPage.qml
+++ b/mu4/userscores/qml/MuseScore/UserScores/internal/ChooseInstrumentsAndTemplatesPage.qml
@@ -56,14 +56,10 @@ Item {
 
         ChooseInstrumentsPage {
             id: instrumentsPage
-
-            anchors.fill: parent
         }
 
         ChooseTemplatePage {
             id: templatePage
-
-            anchors.fill: parent
         }
     }
 }
diff --git a/mu4/userscores/qml/MuseScore/UserScores/internal/KeySignatureListView.qml b/mu4/userscores/qml/MuseScore/UserScores/internal/KeySignatureListView.qml
index 458b8cd44cfe..eadc31076282 100644
--- a/mu4/userscores/qml/MuseScore/UserScores/internal/KeySignatureListView.qml
+++ b/mu4/userscores/qml/MuseScore/UserScores/internal/KeySignatureListView.qml
@@ -9,9 +9,6 @@ GridView {
     
     property var currentSignature: null
 
-    anchors.left: parent.left
-    anchors.right: parent.right
-
     height: contentHeight
 
     clip: true
diff --git a/mu4/userscores/qml/MuseScore/UserScores/internal/KeySignatureSettings.qml b/mu4/userscores/qml/MuseScore/UserScores/internal/KeySignatureSettings.qml
index f7b6ecb14014..ecbf6d8bda37 100644
--- a/mu4/userscores/qml/MuseScore/UserScores/internal/KeySignatureSettings.qml
+++ b/mu4/userscores/qml/MuseScore/UserScores/internal/KeySignatureSettings.qml
@@ -51,7 +51,7 @@ FlatButton {
     StyledPopup {
         id: popup
 
-        implicitHeight: column.implicitHeight + topPadding + bottomPadding + 40
+        implicitHeight: 300
         implicitWidth: 724
 
         arrowX: root.arrowX
@@ -95,8 +95,6 @@ FlatButton {
                 anchors.left: parent.left
                 anchors.right: parent.right
 
-                height: childrenRect.height
-
                 currentIndex: bar.currentIndex
 
                 KeySignatureListView {
diff --git a/mu4/userscores/qml/MuseScore/UserScores/internal/ScoreInfoPage.qml b/mu4/userscores/qml/MuseScore/UserScores/internal/ScoreInfoPage.qml
index be0bde68dcbd..e9986595650a 100644
--- a/mu4/userscores/qml/MuseScore/UserScores/internal/ScoreInfoPage.qml
+++ b/mu4/userscores/qml/MuseScore/UserScores/internal/ScoreInfoPage.qml
@@ -52,10 +52,8 @@ Item {
         AdditionalInfoView {
             id: additionalInfo
 
-            anchors.left: parent.left
-            anchors.right: parent.right
-
             Layout.preferredHeight: 150
+            Layout.fillWidth: true
         }
 
         SeparatorLine { }
@@ -63,8 +61,7 @@ Item {
         GeneralInfoView {
             id: generalInfo
 
-            anchors.left: parent.left
-            anchors.right: parent.right
+            Layout.fillWidth: true
         }
     }
 }
diff --git a/mu4/userscores/qml/MuseScore/UserScores/internal/TimeSignatureSettings.qml b/mu4/userscores/qml/MuseScore/UserScores/internal/TimeSignatureSettings.qml
index 80c3bc3acdbe..bfef8bba2bfc 100644
--- a/mu4/userscores/qml/MuseScore/UserScores/internal/TimeSignatureSettings.qml
+++ b/mu4/userscores/qml/MuseScore/UserScores/internal/TimeSignatureSettings.qml
@@ -28,7 +28,7 @@ FlatButton {
         Connections {
             target: model
 
-            onTimeSignatureChanged: {
+            function onTimeSignatureChanged(timeSignature) {
                 timeSignatureView.numerator = model.musicSymbolCodes(timeSignature.numerator)
                 timeSignatureView.denominator = model.musicSymbolCodes(timeSignature.denominator)
             }
diff --git a/mu4/userscores/view/templatesmodel.cpp b/mu4/userscores/view/templatesmodel.cpp
index 38a36e6bf67b..aca1c9b1e89c 100644
--- a/mu4/userscores/view/templatesmodel.cpp
+++ b/mu4/userscores/view/templatesmodel.cpp
@@ -31,7 +31,7 @@ void TemplatesModel::load()
 
 QStringList TemplatesModel::categoriesTitles() const
 {
-    return m_visibleCategoriesTitles.toList();
+    return m_visibleCategoriesTitles.values();
 }
 
 QString TemplatesModel::currentTemplatePath() const