Open chrome://settings/searchEngines

Hit CTRL+F to "Find on Page" one of the search engines listed at the bottom of the page, out of the bottom of the viewport.

OBSERVE: No results found.

EXPECT: Item found and scrolled to.

If you scroll the page down so the element is in the viewport, then execute the search again, the item is properly found. 

I suspect that this regression was introduced when we switched over to Material for this UI; it's probably doing some fancy Polymer thing where the DOM node doesn't actually exist until you scroll the viewport to it.