I want to modify the initial configuration of QGIS. I read what can be done with the environment variable PyQGIS_STARTUP, but I do not know how to do it.
What I want is to remove some QToolBar, but before I start QGIS.
I know I can remove it using:
main_window.removeDockWidget ([i for i in main_window.findChildren (QDockWidget) if i.windowTitle () == 'Panels'] )