Hi mire000
I can confirm that even in my xfce the loading of the firefox window is as you described.
That never bothered me because firefox is a large application, so it takes time to start.
Note: waterfox e.g. starts without delay.
Some apps are designed to launch various queries before they finally provide their functionality.
Although they will then make the app-window available, but it may take some time until the app has completed all queries and goes into user state.
In Firefox e.g. queries that take place before the actual start, such as update-check, addon-check
and so on.
It is not a bug in xfce, that these programs are designed in this way.
Take a look at libre-office, for example : there is a loading-window with state of charge before the actual opening of the application is displayed.
So I think that's because of the program-design themselves, what will be shown on startup – but not xfce.
If the final loading of the program-window is such a big problem for you ……. :
try preload.
Preload is an adaptive, pre-reading demon.
It observes applications that a user starts, predicts which applications users will launch based on an analysis of these data, and then loads those binaries and their dependencies into memory for faster startup. Note: The system startup speed is not affected by preload.
May be this will help you ….. but have in mind, that queries a program does by using your internet connection might be nevertheless slowing the final user-state .
.