Excellent! My only problem with it is that the added search engines don't get synced by Firefox, so you have to manually add them again if you uninstall and reinstall the browser.

Very useful. Awesome.

Da pra add quantos mecanismos de pesquisa quiser aos padrões do firefox (q já deveria deixar add por padrão)

I'm very happy with this addon. It works perfectly. I'm no longer having any issues at all (I had an issue using an .ico file that I custom specified, but that's no longer an issue). Thank you very much to the developer for creating this! I'm very glad to be able to search my favorite image searches, dictionaries, book searches, etc., right from the address bar. It really helps to save time. Great work! :)

Норм добавляет любой сайт в поиск но не ватает поддержки андроид версии и жаль что нельзя задать поиск через гугл или яндекс по сайту

Something to be ware of (as noted when using the addon): it uploads your custom url to file.io due to a technical limitation in Firefox...

Poorly support. Author will close your issues and ignore errors. It allows you to use invalid (unsupported by firefox) image formats.

This is awesome! I missed Chrome's search engine handling when I migrated to Firefox and this extension has filled the void perfectly. It also shows that even such a simple extension can be really pretty! :)

Was great when it worked. Nowadays, I get an error each time I try to add a new search engine: "Firefox could not download the search plugin from:
https://file.io/XXXXXX". I have switched to the "Search Engines Helper" which also uses file.io, but works fine on my system.

UPDATE: in response to dev's question: I can visit that file.io page with no problem. The Search Engines Helper addon also uses file.io as yours does, but it works for me.

UPDATE 2: Note that I can actually manually access the file.io URL that the "download error" dalog gives me by entering it in the URL bar -- I see the source of the XML file. Hope that helps!

UPDATE 3: After updating to new version (1.8), all is working properly again, so I have revised my lowered rating to reflect my true opinion of this very useful add-on.