Confirmed this works for me. The advanced search buttons aren't popping up as per normal, but hitting enter rather than clicking the magnifying glass works exactly as chrisj describes for me.I've been having the same problem using Chrome on my laptop. Found a workaround. Type in your search term then use the Enter key (don't click on the magnifying glass). You get the crude results, then if you click on Search Again, you get a page with all the search options.
Yes, I have something in the text box to search from - either typed, or selected from a drop down of previous searches (that seems old).That error means nothing was in the search field when clicking the search icon or pressing enter on the keyboard.
Can you confirm if you enter a search term you get search results please??
But otherwise I too am not getting the advance search modal in the latest chrome - it must be deprecation of a html method in Chrome.
I recently got another curious bug like that out of nowhere on another site I work on occasionally.