Toggling the window re-renders UI and makes is lagging

[ivanjaros]

Quite some time ago, some change was introduced that caused the program to always re-render the window whenever it was maximised from minimised state. And it still has not been fixed.

To reproduce this, simply open Heidi, minimize it into task bar, then maximize it again, the window will be lagging a bit because it renders the UI. I would guess what is going on is that as the window is being maximized form minimised state, each increase in size, until it covers the entire screen, re-renders the UI, which caused the lagging effect. So I would guess there is no proper scaling of the UI but rather the used UI library is re-rendering the elements whenever window size changes and so when it goes from 0px*0px to full hd screen or 4k screen it re-renders the window as many times as there are pixels. But this is merely my guess. It's completely inconsistent with Windows behavior for any other programs.