Problem
For no obvious reason timesheet gadget shows empty white frame. No configuration changes have been made and in none of the dashboards where this gadget is used data is available.
Solution
It is still not clear why it's happening and how to fix that.
All I can suggest is to try to reenable add-on or uninstall the add-on, remove jira-timeshet*.jar files from your Jira home, see also: https://confluence.atlassian.com/upm/uninstalling-apps-273875709.html, and then install again, or restart Jira or recreate gadget on dashboard, or try to ask Atlassian Support for help, explaining that gadget most likely can not load its configuration for some reason, and probably they can help to figure out the root cause.
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