Cloning from bug 50897 comment 2:
In the old editor, I would simply use TAB to reach the edit summary, type my
edit summary and press ENTER to activate the "Save page" button and save. If I
wanted to mark the edit minor, then I could type my edit summary, press TAB,
SPACE, and then ENTER to "Save page".
I can see that the new box for entering an edit summary allows newlines to be
entered. I am not sure this is a good idea, because I just used a WSYIWYG
editor and now "What I see" - well-formatted paragraphs describing my edit - is
not going to be "what I get" - everything smashed on one line in the article
history. But that is perhaps grist for another bug mill.
It seems that the "Save page" button never receives caret focus if I use TAB to
try to get there. This would seem to have accessibility ramifications.