Help: Links open in new windows after updating DNS

ecently updated DNS for my organization's website to point to our new domain. After making the change, suddenly certain links on our Plone-based website are opening in new tabs when they never did before. Does anyone know how to fix that? We are using Plone 3.1.7. I'm confused as to why updating the DNS affected links at all.

Tried changing the "External links open in new windows" setting, thinking maybe these links were being considered external. Did not make a difference.