Why don't Firefox and other apps honor my Windows XP settings?

Question

Recently for convenience I set up Windows XP to "Automatically move pointer to the default button in a dialog box" (via Control Panel => Mouse => Pointer Options).

For most dialog boxes (e.g. Windows file delete confirmation, Outlook empty deleted items) Windows will follow this directive and automatically position my cursor above the default button, but some (notably Firefox, if for example I try to close the browser, Clear Recent Browsing History, or various other tasks) won't move the cursor.

Can anyone with Windows programming expertise clarify whether this is happening because Mozilla "rolled their own" objects rather than deriving from MFC, which is presumably why this action is successful on Windows own and other Microsoft applications? Or is there some reason this occurs which is completely unrelated to how each respective app was built?

Answer 1

I don't know definitively, but I would guess it has something to do with the Windows button style which specifies the default button. If Firefox is not setting this window style on their button (which they probably would not, if doing their own UI style for the default button), then Windows would not be aware of it, hence the behavior. Just a guess, though.

For reference: http://msdn.microsoft.com/en-us/library/bb775951%28VS.85%29.aspx (BS_DEFPUSHBUTTON)