When you exit Firefox, your updated preferences should be saved, but there are some possible reasons for this to fail or be ignored. Our support article "[[How to fix preferences that won't save]]" describes how to investigate most of them. ''If the bad new tab page is associated with an add-on or other software you removed, it's possible that some of the unwanted software was left behind. Let us know, in that case, we can provide additional suggestions for cleanup.'' One other problem users have reported is with utility programs such as Advanced SystemCare with features to protect against unwanted browser settings changes. They basically roll back all changes, wanted or not. If you use that tool or other software with a home page protection or browsing protection setting, you may need to disable that until after you've got Firefox working the way you want it.

That worked perfectly, Thank you