Also not sure if you would also like the Content-Type to be switched to application/json as originally reported in #89.

I'm wondering if restricting to 404 only makes sense, what do you think?

It may not be necessary, that was just the minimal change.

I changed it to always add headers, but it may be good to also always return JSON, see #111.

+1 to always return JSON but it should be complementary to the http code I think.

For this PR, I'm +1 with the code change itself, but I think the commit message needs to be adjusted :)

Ah right, fixed now.

Thanks for this! :)