If you have Jira Issues mapped to Salesforce Cases, Connector for Salesforce & Jira automatically aggregates comments from a Salesforce Case that has been associated with a Jira Issue.
Though pulled from Salesforce, these Salesforce Comments are not stored in Jira.
Viewing Salesforce comments in a Jira Issue
Go to a Jira Issue where you've already associated a Case with.
Scroll down and click on the Salesforce Comments tab in the Activity section.
If the associated Salesforce Case has any comments, they will be shown here.
A Salesforce Comment is displayed with a tag to show whether it is Private or Public. Click on the upper section of the Salesforce Comment to expand or contract the comment panel.
Viewing Chatter (Case Feed) comments in Jira
Case Feed (Chatter) comments
Case Feed (Chatter) comments can be posted in a Jira issue via the Salesforce Comments tab.
When someone creates or edits a comment in Jira, a post will be made to Case Feed of the corresponding associated Case object.
You will see Chatter comments in Jira if:
Your administrator enabled Chatter Feed setting in Salesforce.
The Chatter comment satisfies Jira comment privacy and hashtag filters set by your administrator.
The Chatter post is made in Case object (another object is not supported).
Nested comments
Replies posted to Case Feed (Chatter) comments are automatically nested in Jira but are expanded.
Click View Replies to expand all available replies from the Case Feed (Chatter) comments: