About the ToolbarButtons, overflowing issue…
I am struggling with the same problem.
I fixed it by adding a CSS property to the the Toolbar.
// In the opening event of the WebToolBar:
Var ws As New WebStyle
ws.Value("overflow") = "clip"
Me.Style = ws
Now, when I resize the browser-window, any overflowing buttons will be hidden.
But, what should happen, is the hamburger-menu to appear, when clipping occurs, right?
Only when the window is at a “critical” small width, the hamburger appears. But, that happens too late, I think.
@Ricardo_Cruz, is this clipping (instead of “Mac Donalding” 
) an expected behavior or a minor bug?