Issue Summary

This is reproducible on Data Center: no

Customer is trying to send a comment to Jira through their Github integration. This is working, but they are also trying to use this functionality to get the comment to @ mention a specific user. 

https://github.com/marketplace/actions/jira-add-comment

More specific mentions are passed as plain text when using https://github.com/atlassian/gajira-comment with below formats:

User accountId:xxxxxxxxxxxxxxxxxxxxxxxx 

User @aanderson 

Steps to Reproduce

1. Send POST to the rest v3 API method
   URI- https://<domain-name>/rest/api/3/issue/{issueKey}/comment

request body- 

 
{
"body":{
"content":[
{
"content":[

],
"type":"paragraph"
}
],
"type":"doc",
"version":1
}
}
 
The API would use a JSON payload to add the comment and the mention won't work.

Expected Results

User ba8dea20973f  has made a comment on this issue

User 45f9b4c1f1cc  also has made a comment

Actual Results

User [~accountId:xxxxxxxxxxxxxxxxxxxxxxxx] has made a comment on this issue
User @aanderson also has made a comment 

Workaround

Go to the issue and add the mention manually. However, if multiple issues need to be updated to notify a user or group, this is a non-efficient solution.