Firefox browser 52 is the version on my computer and was bundled with my version of the Linux operating system. I have not been able to upgrade. I was told that I might have to remove the browser and then install a later version, but Firefox, when bundled with certain versions of Linux, will not be completely removed, and then a new version of Firefox is impossible to install. I and others have experienced this in the past, so I need to simply upgrade the browser I have to at least version 57. Please give me instructions that will work. Thank you.