The best grammar/spelling checker out there. The only thing missing is the frequency of updates with new features, which could follow the same routine as Chromium.

last few months its been terrible. addon not working at all. not show on any website. cant turn on or off. i need to reinstal it everyday to work for an hour. will be deleting. to bad as i had it for years

nice one

too intrusive

Maravilhoso, fabuloso!
Perfeito.

Funciona como se espera. El plan gratuito es suficiente para un usuario normal de redes o para estudiantes, también.

The best language and writing tool i have seen in my life.

thank-you for every your support

The best out there without a doubt!

I'm very concerned about privacy with this extension. As an example of what they collect (from their privacy policy).
Usage information (such as the date and time of visits, pages viewed, links to/from any page, and time spent in a session)
Device information (such as your internet protocol (IP) address, Internet service provider, operating system, computer model, language settings and CPU details, referrer URL, time zone information, data volume transferred, access status/ HTTP status code, and web browser type).
Inference Information about your usage of LanguageTool (such as whether you are a frequent document uploader or user of a particular feature). Location information (approximated, based on your IP address).

Almost none of this has anything to do with helping to check spelling and grammar and it goes way beyond what anyone should be willing to share to any company, let alone an extension.