Adding a period to the end of the FQDN in the 'Server address' box in the Windows HC app results in SSL errors

Summary

Adding a period to the end of the FQDN in the 'Server address' box results in SSL errors in the Windows app.

Environment

HipChat Windows app v4.26.163

Steps to Reproduce

1. Open the HipChat app
2. Select 'Get Started' under the 'Log in to a HipChat team Server' section
3. Enter in a valid HipChat Server FQDN and add a period at the end of it. (i.e chat.mycompany.com.)
4. If valid, the login page will appear and you'll see a red lock at the top of the page.
5. Upon logging in, you'll receive an error:
   

Notes

Does not appear to affect the Mac app, but does affect the Linux app (see HCPUB-1340)

Workaround

Remove the period from the FQDN.