Open a navigation folder, a header item that holds a list of pages. On desktop this clicks the folder button in the header; in the open burger menu it follows the folder link.
Examples
When I open the "About" navigation folder
When we open the "About" navigation folder
And I open the "Shop" navigation folder
When open the "Services" navigation folder
And we open the "Resources" navigation folder
Pattern
When(/^(I |we )*open the "([^"]*)" navigation folder$/, …)
Part of @webship-js/squarespace-steps (github.com/webship/squarespace-steps), a step pack for Webship-js 2.0.x.