Jira issues can be unlinked (removed) from requirements. In the specific requirement's details window, make sure the correct requirement version is chosen. Click on the task icon on the right side vertical menu. Both Xebrio tasks and Jira issues linked to the requirement version will be listed here.
To unlink a Jira issue from a requirement, click the vertical menu for the specific Jira issue and select Remove. Note that this issue, though unlinked to a requirement, will still be available in the Xebrio Tasks module.
Depending on a user's project permissions, they may be able to view all the project requirements and linked Jira issues, or only a subset of both. Users will need view and edit permissions in the requirements and tasks modules to link/unlink Jira issues, and will need access to the Jira project for which those issues are linked. Project owners manage the Xebrio permissions for project members.