I visited this site where I was able to set the language in the main page. When I clicked on the language link I got an URL like
site.com/index.php?lang=us and was redirected to the home page. On the navbar I could see the USA flag, and when I looked into the HTML code I saw the session value
us in the image src.
So I went back to the main page and set the lang value to
site.com/index.php?lang=test, got redirected, and it really changed the session value. The image on the navbar didn't exist and it was showing nothing.
Could this kind of thing affect the site in some way?