Thank you so much John, I'm trying your solution. Based on your answer, it seems like this problem is not because of something special in my computer. Does that mean this problem occurs on every other computers running Ubuntu with gnome (Ubuntu 18.01) ? (I'm new to Ubuntu, so may have some silly questions :-)
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1787600 Title: kernel: [ 6230.503218] audit: type=1400 audit(1534512537.321:398960): apparmor="DENIED" operation="open" profile="snap.gnome-system-monitor .gnome-system-monitor" name="/run/mount/utab" pid=2265 comm="gnome- system-mo" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apparmor/+bug/1787600/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs