Good news! Worklogs - Time Tracking and Reports team have just released a new version, and since you use Jira Server you can decide to upgrade at any time! All that is needed is a click of a button in the Apps management screen on your instance!
Improvements
Improved performance for retrieving work logs for issues with large number of work logs
Bugs:
Fixed an issue with exporting a small dataset on larger instances (>90k work logs for issues with >20 worklogs)
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