I had the same issues of triggering downloading the result with Firefox on MacOS, when doing a

link_to(some_path(format: :turbo_stream))

However, there is a very simple solution to that, which triggers turbo_stream correctly. This way, you even can get rid of the 'turbo'-controller:

link_to(some_path, method: :get)

Correction to my last answer: You need to add '@rails/ujs' first