Problem
While trying to edit the Gadget on an existing Dashboard, the user receives an error message: “The data source doesn't exist, or you do not have permissions.” Users are able to edit the dashboard by selecting “This Jira Instance Datasource,” but configuration changes for gadgets affect the dashboard.
The issue only appears when more than one or two persons have edit permissions on a dashboard.
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Solution
To collaborate on the same gadgets with the same datasource, create a new datasource with the permission of “My organization.” Thus, any logged user in that instance can use that datasource.
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