[ktpsns]

Especially, it takes one line in almost all toolkits to create Standard dialogs such as

   window.alert("Hello world");

You can show such windows even from the terminal in Powershell, Linux, OS X. With one line of code.

It's not everything so broken...

[greggirwin]

A message box is not the same as a dialog with user controls.

[ktpsns]

All major toolkits have confirmation modal windows, input modal windows, etc as single line "calls". Of course it's not a "custom window" but it is one.