As well put by @LucasWerkmeister:
On Wikidata, when I search for an item and the results are ambiguous (e. g. similar works of art), I can middle-click on them to open the items and inspect them more closely, since the search results are links. Here, even though the individual search results have a “pointer” cursor, they’re not actually links and I can’t follow them. If I want to find out which item is the correct one, I have to figure that out on Wikidata and then copy the item ID and paste that here.
The workaround here is that 'choosing' a value does not save the claim, and gets you a hyperlink to the Q-item, so you can investigate the value that way ; but a middle-click would be much appreciated. :)