Is there a reason we can’t search for pages when adding links to sidebars/widgets? (explained in post) – Please help lol

So, when we add a link to a page or post, we can search for the page (or paste in the URL).

But, when I add a link to a sidebar, I can only paste the URL in… Even though it says "Search or Enter URL".

Is there something wrong with my site, or is this just a thing we aren't able to do?

And if we can't, why does it say "search" in the bar… lol

Thank you in advance for any help with this,
E. Rains.