Old search results won't disappear

[nscyclone]

Steps to reproduce:

• Visit a page built on the latest ex_doc release (e.g. https://hexdocs.pm/ecto/Ecto.html);
• Type something into the search field, press Enter. Repeat this at least two times.
• Close the last results;
• Scroll to the bottom of the page: all the results except for the explicitly closed ones will be present.

Expected behavior: the old results should be removed after every attempt of search.

Example: