Hi @Warren, David ,
Microsoft Teams creates a copy of the file in the "Microsoft Teams Chat Files" folder when you share or receive a file in a chat. This is a default behavior and cannot be turned off. However, you can avoid working on the wrong file by ensuring that you and your team members are always working on the file stored in SharePoint.
To access the file stored in SharePoint, you can navigate to the associated site directly from Microsoft Teams. You can do this by clicking on the ellipses (...) on the top right corner under your profile picture while in the Posts tab of a channel, and selecting Open in SharePoint. Alternatively, you can access the file via SharePoint Online by going directly to the site using the common URL structure: https://<tenant-name>.sharepoint.com/sites/<Team-name>/Shared%20Documents/<channel-name>
And there is a blog for your reference:
https://efficiency365.com/2022/06/30/share-file-in-teams-chat/
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