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By default, Bitbucket selects the most recently used repository on the create branch page. Similarly, when linking Bitbucket projects to Jira projects, the most recently used repository of the configured project is selected.
App's default behavior:
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Jira project -> Bitbucket repository relationship by scanning commit messages for Jira issue keys
If you want a one-to-one relationship between Jira projects and Bitbucket repositories, Create Branch Wizard for Bitbucket selects the correct repository based on the issue keys it finds in the commit messages when you create a branch from JIRA.
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If you want to override this default behavior or want to make the create branch page settings dependent on other factors like the JIRA component of the issue, you can define so-called branch mappings.
Extend App's default behavior: use branch mappings
With branch mappings, you can configure for which JIRA project, component and issue type which branch name, branch type and branch from values should be filled in by the app when you create a new branch from JIRA.
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