I want to switch language in my Drupal 8. My language detection is URL. But I don't want users to be able to override the language switch by typing in the address bar.
For example www.mysite.com/ (default English) and when I type www.mysite.com/ja (Japanese) and then it switches to Japanese. But I want only to switch language by clicking the language switcher. What would be a starting point to implement this?