Very slow painting many components LCL/win32

[bobby100]

@marcov
I also have a similar situation on Windows, but it works perfect on Linux with QT5 widgetset.
I have a couple of tabs, with some 50 sliders on one of them. Changing the tab shows the same effect you described (the painting begins on bottom right, and ends on top left corner of the tab), and it is so only on Windows. As I said, on Lin/QT5 works perfect.

Edit: the sliders I use are from EyeCandy package.

Can you test with Qt5 under windows ? Is there any difference between win32 and qt5 widgetsets on windows ?

Any link for some slim version of the QT5 for Windows? The download I've found is 3,7GB