No title bars in some applications (LXQt, Tumbleweed)

Hello.
I have installed Tumbleweed today: “Generic desktop” role with LXQt pattern.
There is one problem: no title bars in some windows, for example: Ark, FeatherPad, LXQt File Archiver, PCManFM-Qt File Manager, QTerminal, Konsole, LXQt Configuration Center. They are all placed at the top left corner.
At the same time some windows have title bars: Firefox, all individual LXQt settings applications, PulseAudio Volume Control, Advanced Network Configuration, Openbox Settings. They are placed centered.
Screenshot of FeatherPad attached.
How can I diagnose and fix the problem?

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