The AssertThat Global configuration & Reindex page can be found under the Jira Administration pages - Manage Apps:
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On demand a reindex may be required of AssertThat to resyncronise the Jira issue properties. Certain features use AssertThat Jira issue properties such as Dashboard Gadgets and Traceability charts.
AssertThat Global reindex will reindex ALL projects. The duration of the task is dependent on the number of Jira Issues and linked AssertThat Scenarios.
On clicking Start Now Reindex will initially Gather Reindex stats before proceeding with the Reindex process.
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