Longer than that. I’ve had it shut off for the last 4 years because it actively made things worse and has been ineffective at best. Now it doesn’t underline spelling mistakes probably 70% of the time. Highlighting misspelled words hoping for a quick suggestion help is a gamble if it recognizes the misspelled word at all.

I remember it working fairly decently a decade ago, but it’s been a downhill slide for a long time now.