On your support page: https://www.dynadot.com/community/help/question/SPF-records
I'm stuck at step 3: 3.Check the box next to your domain name(s) and click on the "Name Servers" icon.
Reminder: I do NOT use javascript, for security reasons. The number one reason I use DynaDot is that you're one of VERY few registrars that has core functuality working without js.
P.S. Has DynaDot considered making the site ADA compliant? Usually when icons are invisible, it's an issue with IE's accessibility settings, so I turn it off, get my eyes burned out (aqua on white?!?), find the missing screen element, then restore. It is a huge timesink. :(