Current State:

Articles displayed in the narrow style, and in the edition mode the "Wide view" option does not work with in the customer portal for Article. 

("Make full width" icon on the create article screen In JSM knowledge based section is displayed the article in the narrow style, and in the edition mode the "Wide view" option does not work. )

Proposed Future State:

"Make full width" icon on the create article screen.
here the article is displayed in the narrow style, and in the edition mode the "Wide view" option as well in Customer portal