When selected an "Unknown word" (for example double-clicking) or using the cursor to highlight, a modal window requiring "Add to dictionary" or "Ignore" with a mouse click. Must be able to or turn off without using the mouse; cannot use as it comes up too much.
This sound similar to editing experiences I'm having, so I will chime in here. When I highlight in Word, I cannot make edits. I did not have this feature until I recently installed ProWritingAid Everywhere for Mac.