For the following steps you need Jira Administrator permissions.
The Company Chat App Integration allows you to start a chat with Microsoft Teams or Skype for Business directly from the user profile or hover card.
You can configure the Company Chat App Integration in the administration section at Cog icon > Add-Ons > User Profile Configuration > Integration Options > Company Chat App Integration.
You can choose between an integration for Skype for Business or Microsoft Teams. Only one integration can be activated at a time. To have no integration at all, just disable all the options.
Image 1: Configuration – Company Chat App Integration
If one of the options is enabled, user profiles and hover cards will be enriched with a link for starting a chat with the user.
Image 2: User Profile – Company Chat App Integration
Information about Performance
Be aware that Skype for Business or Microsoft Teams link contains the user's email address. If you limited the rendering of the email address to administrators in the security settings, you should probably also disable this option.