Although it can save you a lot of time, the Version & Component Sync add-on app can also be very destructive in case the add-on app is not configured properly. The Version & Component Sync add-on app will alter the linked target project version configuration as soon as the link has been created. This can include deletion of versions, which also removes them from any associated issue.
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Make sure you are fully aware of how the add-on app configuration works and that you have confirmed that it is configured and working as expected.
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