Their business model may be OK, it's just something that you need to be aware of (and a lot of people I've talked to aren't).
From the privacy policy:
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We collect this information as you use the Site, Software, and/or Services:
- User Content. This consists of all text, documents, or other content or information uploaded, entered, or otherwise transmitted by you in connection with your use of the Services and/or Software. For more information about how we care for and protect your User Content, please see our User Trust Guidelines.
You could try a locally self-hosted instance of https://languagetool.org/ to avoid sending all your online typing to an extra party.
Not sure if it's missing any notable features of the SAAS product.
From my relatively experience of Grammarly (I had an account a couple of years ago) a self-hosted instance of LT is slightly better than Grammarly "free" but doesn't have the extra analysis offered by Grammarly's paid accounts.
Can indeed be recommended as substitute to grammarly free.
I give them the credit that they fixed it within hours, but should the project-zero team fill in for their testing team ? :-) https://bugs.chromium.org/p/project-zero/issues/detail?id=15...
It just doesn't mean what you intended :)
Until now I had assumed Grammarly was for people who should have learned to write better in school. I wonder if there's a Dutch Grammarly? :P