Screen artifacts, not getting cleared until window is resized

[Demolishun]

Qt versions I am seeing this in: 5.15.7 and 5.15.5 (have not tested 5.15.2)

Here is some minimal code that causes this (copied code causing this from another project into minimal project for this test):

import QtQuick 2.15
import QtQuick.Controls 2.15
import QtQuick.Window 2.15

Window {
    width: 640
    height: 480
    visible: true
    title: qsTr("test screen tearing, lack of update")

    Action {
        id: showconfiguretankimageaction

        onTriggered: {
            configuretankimage_loader.sourceComponent = configuretankimage_comp
            configuretankimage_loader.item.show()
        }
    }

    Button {
        text: "open window"

        action: showconfiguretankimageaction
    }

    Loader {
        id: configuretankimage_loader
    }

    Component {
        id: configuretankimage_comp

        // chart to show and adjust threshold of received raw data
        Window {
            id: configuretankimage

            readonly property real horizontalZoom: tankimage_scaled.horizontalZoom
            readonly property real verticalZoom: tankimage_scaled.verticalZoom

            title: qsTr("Configure Tank Image")

            width: 500
            height: 500

            Column {
                width: parent.width

                Slider {
                    id: hzoomslider

                    orientation: Qt.Horizontal
                    width: parent.width * 0.8
                    anchors.horizontalCenter: parent.horizontalCenter
                }
                Slider {
                    id: vzoomslider

                    orientation: Qt.Horizontal
                    width: parent.width * 0.8
                    anchors.horizontalCenter: parent.horizontalCenter
                }
            }

            Component.onCompleted: {
                let tempx = mainwindow.x - width - 10
                x = tempx >= 0 ? tempx : 0
                y = mainwindow.y + mainwindow.height/2 - height/2
            }
        }
    }
}

I updated both my video drivers to latest for my intel and nvidia gpus (laptop).
My main window in my other app sometimes flickers and doesn't update. I have never seen this issue at work when working on a laptop in windows or linux. I don't know if this is related to my machine or qt.

Stuff gets weird when I scroll the sliders. It is only fixed when I resize the window.

Here are examples of what gets weird:

I played with this a bit and can get the subwindow into a state where it ceases updating and redrawing even after resizing.

No other software that I use on this machine does anything like this. Very confused.

[Demolishun]

Stranger and stranger. This causes issue still:

import QtQuick 2.15
import QtQuick.Controls 2.15
import QtQuick.Window 2.15

Window {
    id: mainwindow

    width: 640
    height: 480
    visible: true
    title: qsTr("test screen tearing, lack of update")

    Action {
        id: showconfiguretankimageaction

        onTriggered: {
            configuretankimage_loader.sourceComponent = configuretankimage_comp
            configuretankimage_loader.item.show()
        }
    }

    Button {
        text: "open window"

        action: showconfiguretankimageaction
    }

    Loader {
        id: configuretankimage_loader
    }

    Component {
        id: configuretankimage_comp

        // chart to show and adjust threshold of received raw data
        Window {
            id: configuretankimage

            title: qsTr("Configure Tank Image")

            width: 500
            height: 500

            Column {
                width: parent.width

                ScrollBar {
                    orientation: Qt.Horizontal
                    width: parent.width * 0.8
                    height: 20
                    anchors.horizontalCenter: parent.horizontalCenter
                }
                Slider {
                    id: hzoomslider

                    orientation: Qt.Horizontal

                    width: parent.width * 0.6

                    from: -1.0
                    to: 1.0
                }
                /*
                Row {
                    width: parent.width * 0.8
                    anchors.horizontalCenter: parent.horizontalCenter
                    Text {
                        text: hzoomslider.value.toFixed(2)
                    }

                }
                */
                Slider {
                    id: vzoomslider

                    orientation: Qt.Horizontal
                    width: parent.width * 0.8
                    anchors.horizontalCenter: parent.horizontalCenter

                    //from: -1.0
                    //to: 1.0
                }
            }

            Component.onCompleted: {
                let tempx = mainwindow.x - width - 10
                x = tempx >= 0 ? tempx : 0
                y = mainwindow.y + mainwindow.height/2 - height/2
            }
        }
    }
}

But this magically fixes issue:

import QtQuick 2.15
import QtQuick.Controls 2.15
import QtQuick.Window 2.15

Window {
    id: mainwindow

    width: 640
    height: 480
    visible: true
    title: qsTr("test screen tearing, lack of update")

    Action {
        id: showconfiguretankimageaction

        onTriggered: {
            configuretankimage_loader.sourceComponent = configuretankimage_comp
            configuretankimage_loader.item.show()
        }
    }

    Button {
        text: "open window"

        action: showconfiguretankimageaction
    }

    Loader {
        id: configuretankimage_loader
    }

    Component {
        id: configuretankimage_comp

        // chart to show and adjust threshold of received raw data
        Window {
            id: configuretankimage

            title: qsTr("Configure Tank Image")

            width: 500
            height: 500

            Column {
                width: parent.width

                ScrollBar {
                    orientation: Qt.Horizontal
                    width: parent.width * 0.8
                    height: 20
                    anchors.horizontalCenter: parent.horizontalCenter
                }

                Row {
                    width: parent.width * 0.8
                    anchors.horizontalCenter: parent.horizontalCenter
                    Text {
                        text: hzoomslider.value.toFixed(2)
                    }
                    Slider {
                        id: hzoomslider

                        orientation: Qt.Horizontal

                        width: parent.width * 0.6

                        from: -1.0
                        to: 1.0
                    }
                }

                Slider {
                    id: vzoomslider

                    orientation: Qt.Horizontal
                    width: parent.width * 0.8
                    anchors.horizontalCenter: parent.horizontalCenter

                    //from: -1.0
                    //to: 1.0
                }
            }

            Component.onCompleted: {
                let tempx = mainwindow.x - width - 10
                x = tempx >= 0 ? tempx : 0
                y = mainwindow.y + mainwindow.height/2 - height/2
            }
        }
    }
}

[J.Hilk]

@Demolishun so I tested the "still causing issue" version you posted, and no issue for me on 5.15.7

but its on macOS, if that makes a difference