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When editing a default mapping you can only change the Username property.
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Custom Mappings
Repository user mappings can be created for a particular repository. Custom mappings work in the exact same way as the default mappings, however custom mappings are only linked to one specific repository.
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Both default mappings and custom mappings can be edited on the Repository User Mappings page.
Note that only : Only custom mappings can be created.
Repository
This property specifies which repository this mapping refers to.
Note that this : This property is not shown for default mappings.
Username
The VCS username that Continua will match against the current user. If this username is matched against a VCS username then those changesets and checkins will be linked to the current user.
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