Here is the terminal log.
How do I fix it? What does it do? Is it safe or okay?
Here is the terminal log.
How do I fix it? What does it do? Is it safe or okay?
Nautilus is a graphical application so you ought to use gksudo instead :
gksudo nautilus
When you want to do graphical things with high prilivegies, gksudo and gksu are much more convinient than sudo and su.
In Ubuntu 18.04 gksudo is gone.
Instead, try:
sudo -H nautilus
It is an uncritical message; nautilus should run normally; for reference see this report at launchpad.