Palette is empty after some update + outputs errors

Using Arch Linux x64 with latest updates (5.7.6), KDE-plasma 5.19.2, Qt 5.15.0.
Start Musescore 3.4.2 from console
See palettes bar is empty.
Try to add something - list is empty too.

Looking back at console and see some errors:
Cyclic dependency detected between "file:///usr/lib/qt/qml/org/kde/kirigami.2/styles/org.kde.desktop.plasma/Units.qml" and "file:///usr/lib/qt/qml/org/kde/kirigami.2/styles/org.kde.desktop.plasma/Units.qml"
qrc:/qml/palettes/PaletteTree.qml:539:5: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo() { ... }
qrc:/qml/palettes/Palette.qml:551:13: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo() { ... }
qrc:/qml/palettes/PalettesWidgetHeader.qml:128:5: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo() { ... }
qrc:/qml/palettes/PalettesWidgetHeader.qml:120:5: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo() { ... }
qrc:/qml/palettes/PaletteTree.qml:152: Error: Cannot assign to non-existent property "color"
qrc:/qml/palettes/PaletteTree.qml:398:21: Unable to assign [undefined] to bool
qrc:/qml/palettes/PaletteTree.qml:193:19: QML ItemDelegate: Binding loop detected for property "width"
qrc:/qml/palettes/PaletteTree.qml:288: TypeError: Cannot read property 'width' of null
kf5.kio.core: "Невозможно войти в папку tags:/."
qt.qpa.xcb: QXcbConnection: XCB error: 3 (BadWindow), sequence: 3021, resource id: 14717187, major code: 40 (TranslateCoords), minor code: 0
(output is shortened)