Two-column layout with a sidebar snippet
This desktop layout has a main content column and a 300px sidebar. One snippet sits in the content after this first paragraph, and one sits inside the sidebar between two widgets.
On a desktop viewport the sidebar snippet should classify as a sidebar position and claim id 903, staying exactly where the script is inside the column. On mobile the column is hidden by CSS; the ad still belongs to the script's spot, only the label changes to a content position.
A third paragraph fills out the main column so the content root is measurably a column beside the sidebar, which the geometry gate uses to accept the sidebar candidate.