The information displayed in the Issue Activity section in the Issue view is provided by JIRA, not Tempo
On Server Data Center, you can disable the Work Log tab in the issue view (JIRA Administration > Add-ons > Manage Add-ons > System add-ons > Issue Tab Panels Plugin), but the worklogs will still appear in the Activity tab.
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Atlassian has suggestion issues in their JIRA support system, requesting a change to the information displayed in the Jira provided tabs:
Server Data Center - https://jira.atlassian.com/browse/JRASERVER-41728
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