I utilize PnP Modern Search v4 for a business search solution on data that is administrated in a SharePoint list. In the business solution I display multiple list columns in the search results layout (Details List), and thus need to ensure that their mapped managed properties are included in 'selectedProperties' of the PnP Search Results webpart. Default already a lot of other properties are included in the configuration, some of which are not even present in the SharePoint list, and others that I do not intend to use. So as good citizen I limit the 'selectedProperties' to only "what you need / want to display":
Well, this good citizenship resulted that some behavior was broken: it no longer worked to open a listitem from the PnP Search Results overview. Direct cause was the property 'PreviewUrl' was without a value in the mapped search results Slots, and this was result that I excluded 'Path' from the 'selectedProperties'. Lesson: although good to limit data retrieval to only what you need; you also must have understanding of 'for what purpose you may need'.
See for more details: PnP Modern Search - Slots
