Hello, I am just planing to use firefox for android source code to build a new app with modifications. I am not going to add any new feature in it right now. I just change its name, logo, package name and graphics assests. Does it is legal ? I checked on play store and found that many people have done like that. Such as- https://play.google.com/store/apps/details?id=com.eagle.web.browser.internet.privacy.browser And many more...