There are some parts of the app, such as the course storage page, with nested interactive elements (in this case, the item is clickable to expand/collapse a section whilst hosting a button to download its contents).

According to the WAI-ARIA spec, this is not a valid use of interactive descendants and should be remediated.

This doesn't mean that we need to change anything in terms of UI, but it should be amended in the HTML markup. Some techniques are discussed in this article: Inclusive Components: Cards