Issue Tracking Instance is configuration details to connect with specific issue tracking system like Jira, Azure Boards etc. This information is used to manage Issues - status and / or comments.
To create an Issue Tracking System instance, select the Issue Tracking tab, and click the 
button. To edit an existing instance, Click on an Instance row from the list.
Enter values for the fields as described in the table below.
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Click the Test Connection button to verify the credentials and other connection details. Click the Save button to save the changes. Optionally, click the Apply button to save the changes, but remain on the current screen until the Cancel the button is clicked.