Unfortunately there is no stacktrace from debug mode.
Uncaught SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data error https://redacted/admin/themes/default/js/bundle/product/form.js?1.7.7.4:700 https://redacted/admin/themes/new-theme/public/main.bundle.js:277
This is all i get in the console