I would like to know what is safe to do when another user is editing the backlog

When I get the message "1 other person is simultaneously editing this backlog", I am unclear as to what I should do or not do.

Is it safe to add new stories?
Is it safe to reorder stories?
Should I refrain from editing stories?
Should I refresh the page periodically to see what has changed?

A little bit more direction would be very helpful.