I've been keeping an eye out for any such announcements, and from what I can tell, there is no current plan. They do have a GUI-toggle for it, so it should stay

I've been keeping an eye out for any such announcements, and from what I can tell, there is no current plan. They do have a GUI-toggle for it, so it should stay around at least for a little while, and with Mozilla even still supporting Windows XP, I think, it's valid to assume that they will continue supporting it even for a longer while, but yeah, can't seem to find anything official at this point.