When somebody makes a change to the content item you're currently working on, you get the following notification:
You have 2 options:
- Refresh to see their changes (including comments, workflow changes), potentially losing your work.
- Continue editing, potentially overwriting their changes and risking more editing conflicts.
The safest thing to do is to backup your work and contact your colleague. Together, you can decide who can make the changes first and who has to wait.