Save conflicts
Diagrams do not merge. If two people edit the same diagram simultaneously, one save lands on top of the other, and the point of this page is that nothing is actually lost when that happens.

#What you will see
Situation | Result |
|---|---|
Two people edit, one saves | That save becomes current. |
The second person then saves | Their version becomes current; the first is kept in history. |
You saved and the diagram looks wrong | Somebody else saved after you. Open history. |
#Recovering the other change
Open the diagram's history, find the version you wanted, and restore it, or open it side by side and reapply the change by hand. See Diagram version history.
There is no live co-editing for diagrams. Two people in the same diagram will overwrite each other. Agree who is editing, or split the work into separate diagrams.
#A few things that catch people out
The page can be co-edited normally; it is only the diagram that does not merge.
Nothing is destroyed. Every overwritten version is in history.
Long editing sessions increase the risk. Save and close rather than leaving the editor open.
#Related
Nothing is lost, even when somebody wins.
