Hello how add Drawerhost OnOpen/OnClose event like dialoghost DialogOpenedEventHandler/DialogClosingEventHandler

Describe the bug
The built-in text labels for both the CheckBox and RadioButton controls gradually gets more and more off center as the system's text scaling % increases.

Steps to reproduce the bug

1. Set text scaling to 150% or higher
2. Open the XAML Controls Gallery
3. View any of the CheckBox or RadioButton controls

Expected behavior
The text labels should remain aligned

What would you like clarification on:

I read that Uno renders all controls in Windows style and there is an option somewhere deep in Uno to have some of the controls render in native OS style.

I believe it's crucial to be able to switch an application's (or page's) property to render controls using native styles wherever applicable (and to be able to switch back to Windows style again when

Describe the bug
Currently Files UWP doesn't work properly in high contrast themes and there are a lot of issues.

To Reproduce
Steps to reproduce the behavior:

1. Switch to any high-contrast theme
2. Open and use Files UWP
3. You'll notice that the design is inconsistent and worse

Expected behavior
App should look like any other app in high contrast themes.

**Screenshots