Initial synchronization gives you possibility to synchronize (migrate) Jira Issues and TFS / Azure DevOps (formerly VSTS) Work Items that were created before TFS4JIRA Synchronizer has been installed.
Starting the Initial Synchronization
In order to run the Initial synchronization go to profile view, click the cog icon and select "Start Initial Sync":
A dialogue window will appear and you'll be able to select:
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