This fix is much too simple! I looked through all the various forums and found a multitude of solutions. Some so complicated I didn’t even bother to check them out. Then . . . .
I looked on the WP Dashboard sidebar under Users; and double clicked on Your Profile. At the top of the Profile page is Personal Options, Visual Editor. If you uncheck the box for: Disable the visual editor when writing, it will correct the problem. Don’t forget to update Profile at the bottom of the page.
Much too simple for a Forum!