Use case
Return the sum up of the logged time of the current and the linked issues.
Expression
Create and configure a Smart field using this expression in General parsing mode:
%{round(sum(append(fieldValue({issue.timeSpent}, issuesFromJQL("issue in linkedIssues("+%{issue.key}+") OR parent in linkedIssues("+%{issue.key}+") OR issuekey = "+%{issue.key}+" OR parent = "+%{issue.key})), [0])) / 60 * 100) / 100}
