Dashboard hangs (frozen) while trying save the sections

[leungvi8]

Hi All, 

Appreciate any help. I'm building a custom theme via shopify partner. While working on building out a few home page sections I encountered some issues with saving while making changes to the frontend (user) dashboard. When I hit save, I get the "section saved notification), but the left side - where you can make changes and move the sections becomes frozen, like it's trying to load something. I've attached the chrome dev error messages. Any help would be much appreciated!

Vince