Meeting participants can be invited in two ways

1 way

Automatically

Lets Jira send meeting invitation from orginizer email to all invitees (and external participants with defined email-address). For that select More -> Send meeting invitation, write your message and click on Send button. All participants' confirmations will be send to orginazier email.

In this scenario SMTP Mail Server should be configured in such way that would allow Jira to send messages from organizer email-address (otherwise organizer will get error "550 IP-Address is not allowed to send mail from example_mail")

2 way

Manually

1. Create an empty invitation message in your mail program
2. Download invitation file More -> Download meeting invitation and attach it to your invitation message
3. Copy email-addresses of meeting participants More -> Meeting Link
4. Paste copied email-addresses in invitation message and send it
5. Participant will receive invitation file, open it and send answer to meeting orginizer (confirm or deny)

3 way

Other possibilities will be implemented