How to remove off-canvas and theme wrapper for a content type

I'm attempting to create an html email newsletter content type whose content is populated by views. Because the Views Global: Custom text field strips inline styles, I've made custom twig templates for the newsletter content type in my theme:

html--newsletter.html.twig contains only {{ page }}

and

page--newsletter.html.twig contains only {{ page.content }}

While

node--newsletter.html.twig contains the html email markup (views called via twig tweak)

and

views-view-field--newsletter--block_2--nothing.html.twig contains the markup from the views Global: Custom text field.

This all works fine except that the result is still wrapped in two extraneous divs: