Blender doesn't ask 'Do you really want to quit', when I press file -> new When I am working on a .blend file, but didn't press file -> save or file -> save as, then when I want to close Blender, Blender will ask whether I am sure to quit:


However, unlike for example microsoft paint, it doesn't ask this question if I press file -> new or file -> open (thanks to Jan Kaderabek :) ):


It explicitly says "Open the default file (doesn't save the current file)" when I point my mouse on it, but some new users may not know this and open a new file without saving their previous file.

My question: how can I make Blender ask this too when I want to open a new file?
Unfortunately, you can't do this. Notice that Blender uses an operating system specific dialogue box instead of the normal Blender UI. This appears to be more of an operating system thing than a Blender, but it obviously doesn't work with the Blender controls. 

You can see that if you do File > Quit, Blender will open a dialogue box that asks if you want to quit (it is the same whether the file is saved or not). 



This is not a "smart" dialogue. The same applies to the "new file" button. Blender opens a dialogue box, but it is not an OS level "smart" dialogue box.