Text jumps when hitting Return in Inspector Summary

I created a standard outline for my Summary in the Inspector that is longer than the Summary window. When I type text in the Summary window and then press Return, it correctly creates a new line with the cursor at the beginning of the line.
But the page view (the part of the long Summary outline visible in the Inspector window) jumps randomly to three locations: a view in which the cursor is located at the the top of the Inspector window (like a Page Down); a view in which the cursor is located above the top of the Inspector window, so I need to drag it back down to see it (like End of Document); and sometimes no jump at all, just remains in the same location. This only happens in the Summary section of the Inspector, not in the Notes which allows different formatting. If this can’t be resolved, I may just move my outline to the Notes.