Simple, efficient.

Of course, in the Edit viewer, the shortcut is always present, but it does not act. No problem, after the shortcut [clearboth], you type several returns to simulate it. These returns will disappear when you quit the Edit viewer, but the shortcut [clearboth] will do the job.
And the next time you use the Edit viewer, [clearboth] is always present.
It is stable. Very nice.