Works like a charm Rated 5 out of 5 stars
Thanks for the feedback.
Re: MIME types and configurability, JSONovich does not look at file extension, but rather MIME type. I chose to go that route because there is a clear way to set up a MIME type-specific stream converter within Firefox extension components, and generally because I find MIME types more reliable than file extensions in the wild, wild web. The JSON format has but one MIME type, application/json, and so that's all I feel comfortable relying upon. I should note that the unofficial text/x-json type, which I gather gained usage before IANA standardized upon application/json, is also supported by JSONovich.