How does one set JSON Configuration Paramters

Trying to access a JSON File on my NAS and getting the following error:

Seems I need to set a parameter called ‘store.json.all_text_mode’ to true, but it is not clear where one would actually set this parameter?

Admin > Advanced Settings:

Enter “store.json.all_text_mode” into the Support Key box… Click Show

Thank you David, that was rather hidden functionality. Not sure adding that param had the desired effect or not as now I’m experiencing another issue now…may or may not be related: