https://wiki.qt.io/Qt_Coding_Style says:

"Keep lines shorter than 100 characters"

Problem: qmlformat creates lines over 100 characters long. 

E.g. when you qmlformat the attached file, these two lines

        readonly property string minutes:
            "%1".arg(parseInt(progressSlider.value / 60)).padStart(2, '0')

are concatenated into a single line 105 characters long. 

Note: https://doc.qt.io/qt-6/qml-codingconventions.html does not mention line length limit at all, but my understanding is that generic Qt coding style rules would apply in that case. It wouldn't hurt to clarify this in the QML Coding Conventions.