It’s just today that I’ve tried one theory that came to my mind. What if I’d open my markdown posts with LibreOffice, will it check the grammar? Yes, it did. And the LanguageTool (integrated now) extension did work too!
Previously, I did check some paragraphs in LibreOffice. As I was lazy, I’d checked only the ones I was unsure of. For others, I kept the misprints and wrong words too. Not that the tool would re-write the contents for me (which I don’t need anyway), but I think it’s an easy extra step. Now, no need to copy-paste my content here and there, I can just open my file with the other app, check the spelling, and fix at least some typos. I like it.
To open LibreOffice Writer from command line:
libreoffice --writer
So for ranger that’ll be:
:open_with libreoffice --writer