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Idea
If time tracking is activated in JIRA and a user has the rights to browse a certain project, there is no way in JIRA to restrict access to time tracking information, i.e. time logged with all description details as well as work estimates will be visible to a user who has access to issues. Even though you can restrict the right to log time, you can't prevent users from seeing time tracking information, and you can't restrict access to the fields "Original estimate" and "Remaining estimate" (these fields appear even of you do not grant the "work on issues" permission). This might be perfectly okay within a developper team, but probably is generating huge problems if you grant your customers access to a project. There is no proper solution for this as JIRA does not offer this level of permissions.
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