The documentation you linked to is specific for Bitbucket Cloud (hosted at bitbucket.org). For Bitbucket Server where you're hosting the application, we currently use Markdown and support for emoji is being tracked in the following feature request:
As a project manager, I have discovered that different developers want to bring their previous branching method with them when they join the team. Some developers are used to performing individual wo...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
You're one step closer to meeting fellow Atlassian users at your local meet up. Learn more about AUGs