The issue type is a defining property of an issue, it makes no sense to have something that is a "bug" and an "improvement" at the same time, it's one or the other.
So, no. You can only give an issue one type.
You can have many types in a project of course, just check the "issue type scheme" for it.
Hi Atlassian community, My name is Max and I work on the product integration team at Atlassian. I am pleased to announce the early access program for the Jira Cloud add-in for Outlook. This add-in...
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