Rated 5 out of 5 stars

Nice. Easy to use, very straight forward. Add custom engines to a context-menu sub-menu.

As a suggestion to the developer: the ability to convert spaces to pluses, underscores or other common separators would be helpful.

This review is for a previous version of the add-on (1.5). 

Thank you very much for the feedback. Let me explore your suggestion to converting spaces. Currently we are letting the browser to handle the spaces in the given input.