So I'm working on a custom version of windows 10, and firefox is starting to gain popularity, and it is my personal favorite. And because of that, I want it to be the default pre-installed browser on my windows 10 version. But I can't find a way to embed it in the ISO, I don't want to run the installer during the windows 10 installation or after setup, I want it to be pre-installed.

I would like to know where firefox installs, and if possible get firefox's files and put them in the right directories.