Confluence attachments: what actually happens when two people edit the same file

You download a spreadsheet or a work instruction that is attached to a Confluence page, and you start editing it. A colleague, without knowing you have it, does the same. You both finish. You both upload your version.

Here is what Confluence does with that: it keeps both uploads as versions, and the last one saved is the one everyone sees. Nothing merges them.

Last save wins, as described by Atlassian's own community

An Atlassian Community Champion answered exactly this question in January 2023: multiple people can edit an attachment at the same time, but "the last individual to save their edits will overwrite whatever the other individual saved." Each save is kept as its own version, and there is no way to edit an attachment collaboratively in the product as delivered.

(the thread, Brant Schroeder, Community Champion)

So the earlier work is not destroyed. It is sitting in the file's version history. But the page now shows the other person's file as the current one, and whoever lost out has to go looking to find that out.

There used to be a helper, and it was removed

Confluence Cloud once had the Atlassian Companion app, which let people open an attachment in their desktop Office program and save it back. Atlassian removed it from Cloud on 31 March 2022. Its announcement (Removing the Companion app from Confluence Cloud) suggested two alternatives: embed Google Drive files and edit them there, or replace the file by hand, by deleting and re-uploading it.

Two feature requests that asked for warnings or blocking while editing through Companion, CONFCLOUD-65425 and CONFCLOUD-65595, were closed as Won't Fix in October 2023 with a one-line comment that the Companion app was deprecated. Those closures are about a tool that no longer exists. They do not tell you what Atlassian thinks about the problem itself.

Locking is still an open request

The request that does cover the problem itself, CONFCLOUD-2841, "Provide locking for attachments", is still open, with the status Gathering Interest. Until something ships there, whether a team notices a collision depends on the people involved.

What an app can and cannot do about it

Confluence Cloud gives apps no way to intercept an attachment upload before it happens. Nothing, not this page and not any app including ours, can stop the second save from landing.

What is possible is smaller: finding out. Check a file out before you start editing it, so your team can see it is spoken for. If someone replaces it anyway, Attachment Guard notices within a few minutes, tells the person who had it checked out, and can restore the earlier version in one click, with the overwriting version kept in history, not erased.

That is not prevention. It is telling the right person, soon, instead of leaving them to find out the hard way.

Attachment Guard is a Forge app for Confluence Cloud, built and supported by Alzhan Group LLC. Free up to 10 users. See the documentation for how check-out and restore work, or the privacy policy for what the app does and doesn't store.