25- Change the main icon of QGIS

Download icon image

import os

icon = 'qgis_orange.png'
data_dir = os.path.join(os.path.expanduser('~'), 'D://', 'Python_QGIS')
icon_path = os.path.join(data_dir, icon)
icon = QIcon(icon_path)
iface.mainWindow().setWindowIcon(icon)