On every JIRA issue page you can find new "Slack" tab in the Activity section (near Comments). If the issue you are looking at has a dedicated channel assigned you will be able to quickly join the Slack discussion directly from JIRA.
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| Messages may look slightly different than in you Slack client because this view uses a simplified message formatter. Please let us know if the simplified formatter does a really weird thing or is missing support of an important casefeature. |
Moreover you can join Slack conversation directly from here as the input field below the last message lets you send messages back to that channel.
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