Hello @dngood and @Liz , happy Friday!
You can specify redirect target in your typeform embed. More details in the embed lib docs (look for redirectTarget) or in my blog article from last year. You need to use the value _self.
@dngood it looks like you are embedding your typeform directly in an iframe. If you want to use this feature, you need to use our embed SDK.
BTW did you know that our embed SDK supports embedding the typeform in a popup? No need to use a lightbox or your custom popup. More details here: https://www.typeform.com/help/a/embed-your-typeform-360029249212/#h_01FKFTT9N3YHW4C6VEWT7R9C48
However you are more than welcome to use your own if you like it better 😃