Hello @Brendan Yee ,
The Purview Data Map > Source Management > Connection Page is used for creating unique connections to services to use more of Microsoft Purview Data Map's features.
You might use the connection page when creating connections for some workflows or protection policies that require you to make special connections to partner resources.
Find the relevant documentation Here: https://learn.microsoft.com/en-us/purview/data-map-connections-page
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