Manually triggering a user directory synchronization breaks subsequent synchronizations

Steps to reproduce

• Setup LDAP directory in JIRA
• Set synchronization interval to 1 min - the interval shouldn't make a difference, this is just to reproduce it quickly.
• Let the scheduled sync run a few times to confirm it works
• Trigger a manual synchronization

Expected results

• The scheduled sync starts up again based on defined synchronization interval

Actual results

• The scheduled sync does not fire again

Workaround

• 'Edit' the external directory in JIRA and save the configuration without making any changes should bring back the scheduled sync