CI4 upgrade from version 4.2.1 to 4.2.6

If any changes have been made in the new version of the app folder then yes you will need to manually
edit and move your code into the new files in the app folders,.

Please read the change logs they will state what files in the app folder have changed.

I looked at the change logs, but i find no mention of the system folder in the root, maybe i just don't see it