Basic Steps to get Started with Expressions for Jira - Cloud
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Select the workflow transition.
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Click on Add Validator or Condition.
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Select our Plug-in.
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Check the required fields and add.
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Add Title, Expressions, Error message.
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Check out the added Expression.
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Navigate to Manage Apps & open the Expressions for Jira App.
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Expression for Jira helps Jira users to add Jira expressions that allow to customize the behavior of Jira workflow Validator & Conditions.
Install the Plugin from Marketplace
Follow the link for Atlassian marketplace
Download Expression for Jira plugin
Install