If you fix and do not bleach, there is nothing light sensitive present, but if you bleach with no following fix, there are light sensitive materials that can darken. If you fix, bleach and then wash and dry, you still have light sensitive materials present. This is only if you use a Ferri bleach.

I use 2 safelights all the time. One pointed at the ceiling and one pointed away from the enlarger and both at about 5 feet. No fog ever!

PE