Xul’s window.sizemode documentation says:
When a window is minimized, the
sizemode attribute is not updated.
This is done so that if a window is
closed while minimized, its persisted
sizemode attribute wouldn’t be
minimized.
so, is there a way to know when it’s minimized?
The documentation you pointed said:
The window.windowState link is broken. But I could find its documentation. It says you can check if the attribute windowState is equals to the constant STATE_MINIMIZED.