Approval buttons in Outlook look ill-formatted

Summary

The Approval buttons for Approve or Decline in an Outlook email don't look to be formatted correctly

Steps to Reproduce

1. Raise a request that requires an approval.
2. Open up an email in Outlook for the issue that requires the approval.

Expected Results

The button format looks the same as it does in the Approving a Service Desk Request article under the How to approve and decline from email section.

Actual Results

The button formatting in Outlook is boxy and strange. Not sure if this is a limitation on Outlook:

Workaround

Use a different email client to open up the Approver email if you do not want to see the buttons formatted that way or proceed with the approval in the Outlook email.