While working on MDL-80460 (where the default name for the sections for the topics course format will be renamed to "New section" without a number), I missed one behat step for viewing a section using the section number.

There are some similar steps, like 'I hide section "<sectionnum>"', 'I edit the section "<sectionnum"' or 'I open section "<sectionnum" edit menu'. The idea is to create a similar step to display the section.php using the section number.

However, instead of using this approach (which will only work when you're on the course page and in editing mode), a new page resolver can be added to the behat_course class, to add support to something like "When I am on the "Course 1 > <sectionnumber>" "course > sectionnum" page logged in as "admin"".