Lazarus - no borders seen on components in KDE / Plasma (Leap 15.1)

Does anyone know how I can make component borders visible in KDE / Plasma? I suspect there’s a desktop setting I can use, but I haven’t been able to find it. This may not actually be a Lazarus issue, but I didn’t know where to post this. If I remember, it works in IceWM, but I’d rather not use that.