While in this mode, all content should be rendered at the scale of the document's pixels. If zoomed in further, this essentially means that resolution-independence is disabled for the viewport preview and discrete pixels start to appear. This is useful to see how an image will look when it is exported.

• This will be supported only in the Vello renderer.
• The comment // TODO: See issue #320 and the commented-out code beneath it can be reenabled for the UI portion of this change.
• See also Make SVG renderer a preview render mode and take Vello out of preferences #3512.