Mount a component

Mount this component into the DOM so it appears on the product-list page. Take the card component function that returns an element and append it into the container with id product-list. Ensure you clean up any previous placeholder node with class loading-skeleton before appending, and return the mounted element so the caller can attach events.

Before I call mount in production, make mounting predictable: add a check that the container product-list exists, log a clear error if it does not, and make the mount function idempotent so reruns replace the old card rather than duplicating. Highlight any race conditions if async data is still loading.

I mounted the card into product-list during a navigation handler and users reported duplicated items after fast route changes. The engineering manager and the QA lead are watching. I don't know whether to cancel previous mounts, debounce the handler, or use a marker to prevent duplicates. What's the most likely root cause and the minimal fix that stops duplication without refactoring routing logic?

We have six mount functions doing almost the same DOM replacement with tiny differences in cleanup and error messages. This causes bugs when we change how we identify the container. Where are we losing consistency and what habit should we change to make mounts reliable and maintainable across the codebase?