With Qt 6.7, taskbar thumbnails are not displayed. When hovering over a taskbar item, the message error creating screencast "Could not find window id 0" is logged to the journal. Bisected to https://code.qt.io/cgit/qt/qtdeclarative.git/commit/?id=b9bfdea0e2c6721d2306af0ecc44f88da9988957
Indeed. > [ChangeLog][QtQml][Important Behavior Changes] Converting a QVariantList to a QJSValue via, for example QJSEngine::toScriptValue() does not produce a JavaScript array anymore, but rather a better suited sequence object that behaves almost like a JavaScript array. The only difference is that its QJSValue::isArray() will return false now. This is tripping up the isArray check in https://invent.kde.org/plasma/plasma-desktop/-/blob/master/applets/taskmanager/package/contents/ui/ToolTipDelegate.qml#L31
A possibly relevant merge request was started @ https://invent.kde.org/plasma/plasma-desktop/-/merge_requests/1951
Git commit 4648d3b947889eb87db24d932292a9bd2f30aad0 by Vlad Zahorodnii, on behalf of Nicolas Fella. Committed on 25/01/2024 at 10:25. Pushed by vladz into branch 'master'. [applets/taskmanager] Fix showing window thumbnails windows is of type QVariantList, which since Qt 6.7 is not considered an array any more, so this will always be false See https://code.qt.io/cgit/qt/qtdeclarative.git/commit/?id=b9bfdea0e2c6721d2306af0ecc44f88da9988957 M +1 -1 applets/taskmanager/package/contents/ui/ToolTipDelegate.qml https://invent.kde.org/plasma/plasma-desktop/-/commit/4648d3b947889eb87db24d932292a9bd2f30aad0
*** Bug 480313 has been marked as a duplicate of this bug. ***
Git commit 5328675486f605e3d5fcda8efbac16a21a93c44a by Vlad Zahorodnii, on behalf of Nicolas Fella. Committed on 25/01/2024 at 10:26. Pushed by vladz into branch 'Plasma/6.0'. [applets/taskmanager] Fix showing window thumbnails windows is of type QVariantList, which since Qt 6.7 is not considered an array any more, so this will always be false See https://code.qt.io/cgit/qt/qtdeclarative.git/commit/?id=b9bfdea0e2c6721d2306af0ecc44f88da9988957 (cherry picked from commit 4648d3b947889eb87db24d932292a9bd2f30aad0) M +1 -1 applets/taskmanager/package/contents/ui/ToolTipDelegate.qml https://invent.kde.org/plasma/plasma-desktop/-/commit/5328675486f605e3d5fcda8efbac16a21a93c44a