Cannot embed content when editing a content in Page Builder.

Steps to reproduce:
1. Create a new content type with page fieldtype and rich text fieldtype,
2. Create a new content item of freshly created content type,
3. Go to other fields edit view tab,
4. Try to embed a new embedded content item into rich text field.

Expected result:
UDW opens and it's possible to embed a content item.

Actual result:
UDW is not opening and there's an error in the browser console.