[gui] Massive lag after all tabs are loaded

[DCxDemo]

It looks like tab control initializes tab when its clicked for the first time. When all tabs are loaded it generates massive lag when you move the form. find the solution or maybe should remove tab control and replace it with child forms.

[DCxDemo]

Instead of forms gonna create all controls once, then fill the panel based on button clicks, kind of left side vertical stacked menu. Should also be easier to share content between "tabs".