Right-click on the link, most browsers will pop up a context menu with "open link in new tab" as an option.
If you wanted Jira to provide links that did it on a left-click, you'd need to rewrite Jira, thinking of all the places you'd want it to do it, and how most of your users really don't want new tabs all over the place are going to get to the standard behaviour. You don't have access to the code in Cloud, so you won't be able to do it there.
Catch up with Atlassian Product Managers in our 2020 Demo Den round-up! From Advanced Roadmaps to Code in Jira to Next-Gen Workflows, check out the videos below to help up-level your work in the new ...
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