wp, to be clear - I compare Lazarus (win32\64 widget set) compiled app behavior with Qt (using Qt creator) app. Yes, on Win 10 there are no such problem because of the style I suppose. Here the
link to the video, that show what I'm talking about. Don't look at mouse cursor, it's that small because of recording software.
There are no 100% pattern which reproduce this problem. I click left mouse button changing TEdit focus from one to another and sometimes it's reproduce, sometimes not... I'm confused.
And such "bug" has every component which allow text input, even TMemo.