In my Sharepoint 2013 on-premise environment, I have a page that contain a Content Search WebPart.

When I pass some parameters like the firstname or lastname using the wildcard * character in the URL of that page like this :

    http://My_SP_2013_URL/.../Pages/search.aspx?k=firstname:"John*" AND lastname:"*"

The Content Search Webpart shows all the persons with a name begening with John.

I upgrade the same site collection with the same page containing the same Content Search Webpart to SP 2016.

Now when I go to the same kind of URL I got no results.

    http://My_SP_2016_URL/.../Pages/search.aspx?k=firstname:"John*" AND lastname:"*"

It's strange because it works well if I remove the parameter lastname like this : 

    http://My_SP_2016_URL/.../Pages/search.aspx?k=firstname:"John*"

It also work correctly if I insert some charaters before the wildcard in the lastname parameter like this : 

    http://My_SP_2016_URL/.../Pages/search.aspx?k=firstname:"John*" AND lastname:"Smi*"

I try with other parameters and it seems that the search result is always empty when I use the wildcard alone as the value of a parameter in the querystring.

Any idea ?