The close button on macos X windows

[Jean Kaplan]

By clicking the top left red button present on all macos x windows  
one usually closes the corresponding window, but not the program.
In lyx, by clicking this button one leaves lyX altogether. This was  
already somewhat frustrating in formers versions of lyx, but in  
version 1.5, where one can open several windows at the same time (a  
major improvement), this is a real nuisance.  Would it be possible to  
change that, and come back to the standard behavior of macintosh  
windows : clicking the top left red button only closes the  
corresponding window.
If some people prefer the present lyx behavior, it should at least  
possible to change that in preferences.
Thank you
Jean