Run an action of the grid's "Actions" control on the selected rows ("Delete", "Change status > Disable", "Cancel", "Hold"). An action that asks for a confirmation opens a dialog: follow it with I confirm the action.
Examples
When I run the "Delete" grid action
When I run the "Change status > Disable" grid action
And I run the "Change status > Enable" grid action
When we run the "Hold" grid action
When I run the "Unsubscribe" grid action
Pattern
When(/^(I |we )*run the "([^"]*)" grid action$/, …)
Part of @webship-js/magento-steps (github.com/webship/magento-steps), a step pack for Webship-js 2.0.x.