How to enable grammar check on Libre writer?
Spell check is fine but grammar check doesn't work.
I know this is a couple of years old but I just came across this because I'm trying to enable grammar checking on LibreOffice and my copy doesn't even HAVE the "Lightproof grammar checker (English)" option in the exact place you mention.
I am on Ubuntu 20.10. The solution is to install the "libreoffice-lightproof-en" package (I found this simply by browsing apt packages that had "lightproof" in the name). I'm not sure why this package is not installed by default on my distro, but after installing it, the option you describe becomes available.
Unfortunately, I can't tell whether the grammar check works or not, because it does not complain about "The quick brown fox jump over the lazy dog", "I took pill in Ibiza", and other grammatically-questionable sentences. I discovered that most of the options are off by default, so I enabled them, but it ...
Ask a better question. For starters, which language are you trying to check?