WordPress 5.9 added a feature to choose the language dropdown in the default WordPress login page.
This feature is available in the login screen, the password reset screen, and the registration screen. If you do not want this feature or you already have it via custom plugins, you can disable the language dropdown by using a little custom code snippet below:
add_filter( 'login_display_language_dropdown', '__return_false' );
In case it helps, here’s how to easily add custom code snippets to your site.
Alternatively, if you want to use a plugin, there’s a Disable Login Language Selector plugin available for free. The plugin is simple and does this task perfectly.
Did you know? WordPress 5.9 also introduced a full site editing feature.
I hope you found this helpful!