If you are either the creator of Scheduled Issue, JIRA administrator, or the specified Scheduled Issue was shared to you, it is possible to access Scheduled Issue details page by clicking on the Scheduled Issue name in Scheduled Issues table.
To do it, use the drop-down menu cloaked under the "Projects" to access a desired project and then go to the below located "Scheduled Issues" to find "Create" button. It is possible to access Scheduled Issue details page by clicking on the Scheduled Issue name in Scheduled Issues table:
This is how Scheduled Issue details page looks like - it opens when you access any of the listed Scheduled Issues:
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