Page Comparison

Space Sync for Confluence allows you to mention users on external sites if the destination space allows your space to mention.

Have pages edit mode.
Open the mention dialog by clicking the mention icon on the upper right.
Search user to mention.
Click the copy button.
Paste (with Ctrl + V shortcut or right-click context menu on the page body) mention wherever you want to insert mention in the page body.

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FAQ

Question

Answer

When pasting mention, “Unknown user” is shown.

Image Added

This is a limitation of Confluence.
User is resolved when you publish the page. You have to be patient until you pablish the page.

Users on the external site are not found.

The destination space admin explicitly enables mention from your space.