The "J" icon on Safari's tool bar -- does nothing? where's the "Pretty" thing?

[Motti-Shneor]

Well... You can remove the "Pretty" from the name... as clicking the "j" icon on Safari's Toolbar simply does nothing.

I drag a local .json file to the web-address.

I can see its content. Whether it is a "beautified" JSON or compressed-one-string JSON - pressing the J just does nothing at all.

Any idea why?

This is not a web-page, nor web-response to web-request - a simple local .JSON text file, which shows perfectly in other software.

This is MacOS 12.7.1 running on Mac-mini M1 2020, and Safari 17.1.2