Answer
In Salesforce, click ⚙️ > Setup.
If you are using Salesforce Classic, click Setup on the upper right pane.Search for "Package" and go to Installed Packages.
Look for "Jira for Salesforce" and click Configure.
Select Add Connection on the top right and a pop-up will appear.
Enter the Connection Name and Access Token:
For the Access Token, switch over to your first Jira instance to generate a Jira access token.
Navigate to Apps > Salesforce > Connections.
Choose your Connection, then click > API Access Token.
Copy the API Access Token and paste it into the Salesforce screen from Step 4 and click Save.
The first connection created will be marked as "default". Repeat Step 4 - Step 5 to add additional Jira connections from different sites.
For each Jira connection added to this page, you will be able to perform the following operations:
Configure - To configure the settings of the configuration made. For more information, read Configuring settings in the Salesforce Package.
Revoke Access - To revoke the connection made using the API Access Token from Jira.
Make Default - Marking a connection default will make this connection be selected in the Jira components by default. The Jira Comments component will only be able to display issues from the default connection.
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