Reports - Charts and Graphs for Jira Dashboard Free app is the free and limited version of Reports - Charts and Graphs for Jira Dashboard app. Except rate-limiting it has the same set of features. You can reach documentation of the pro app here.
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Free version has a rate limiting of 12 request per 1 minute. If 1 report rendering per 5 seconds. The rate limiting is hit, reporting is limited to 10 issuesbased on your Jira instance, that is, if you and one of your colleagues send report requests to our app within the same 5 seconds the latter report request will not render.