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This settings was added to the appapp’s server version, starting version 2v2.2.x.
By default, there is no verification if configured field is present on project's screens.
Therefore, a user might be able to set a value for a field that is configured for Gantt chart but is not present on Create/Edit issue screens of configured project.
Should you prefer to prevent such behavior, please make sure to check the checkbox 'Screen field check'.
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