It's nowhere near the features and look of Insomnia but a pet project that I work on my spare time it's http://github.com/jsargiot/restman http://github.com/jsa

It's nowhere near the features and look of Insomnia but a pet project that I work on my spare time it's http://github.com/jsargiot/restman http://github.com/jsargiot/restman. The initial need was because Opera didn't had an extension of such kind.