The content of this Space is not the latest version of WBS Gantt-Chart for Jira.
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Unable to display WBS and Gantt chart?
Summary
WBS Gantt-Chart for Jira does not display WBS and Gantt chart. This error is caused by a bug in Jira JRA-37337 ("Batch CSS and Javascript generation causes long delays in page loading after plugin modification") when using Jira 6.0.x, 6.1.x, or 6.2.x.
Workaround
See JRA-37337 for the workaround.