How to turn off spell check hyperactivity of June/July 2018

Sometime probably first week of July 2018, something changed in Spell Check. Now about 20% of all words are being changed -- common words such as "my" becomes "may" "good" becomes "goodbye" "day" becomes "data." It's really nuts.

I only use the physical keyboard -- that's the whole point of a Blackberry!

I have looked for every Setting I can find, and have turned them all off:
Settings > Language & input > Spell checker > off
Settings > Language & Input > Prediction and correction > Auto correction > Physical keyboard > OFF
Settings > Language & Input > Prediction and correction > Auto correction > On-screen keyboard > 30%
Settings > Language & Input > Prediction and correction -- I turned off everything I could find, deleted word lists, etc

What else is going on?

Which device and OS are you using?

Typed on my Q10, SQN100-2, 10.3.2.2813