You could try similar rule
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.
You can try the {{issue.fixVersions.name}} smart value
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.