Full width background image in the welcome and finish dialogs

[Anders]

https://stackoverflow.com/questions/71539145/how-can-i-change-the-width-of-the-image-in-the-welcome-and-finish-pages-in-nsis

[OrHoshmand]

I am trying to create an installer with a backround image that covers the whole width of the welcome and finish dialogs, and another background image that covers the whole headeer in other dialogs, in Modern UI. What lines should I add to the scripts for that?