Parameters for wrapping an existing page in a new split test. Provide 1 or 2 variants. The first variant's page_id must already be attached to a step in this funnel's workflow (that page gets wrapped). The second variant's page_id must be a fresh page (not already used by any step anywhere). No cloning occurs.

Positioning the split

By default (no show_page_step_id), the split lands at the funnel entry — sort_order 0 under the workflow root — with all surviving steps moved into a Root Step after Sequence End convergence sequence positioned right after the split.

When show_page_step_id references an existing show-page step in this funnel, the split is inserted after that step under the same parent, and steps N+1...end are migrated under the convergence sequence. This is the "split between step N and step N+1" shape.