Cyrillic uppercase to lowercase letters in WordPress

The web sites encode Cyrillic uppercase and lowercase letters with different percent codes:

АБВ = %D0%90%D0%91%D0%92

абв = %D0%B0%D0%B1%D0%B2

If the user types a capital Cyrillic letter in the browser address bar, the result is 404 page not found (at least in WordPress 5.2.2 with Avada 5.9.1).

This plugin replaces all occurences of %d0%90 with %d0%b0 in the request, by using add_action( 'request', function ( $request ) { ... } ).

This is applied to all 33 characters of the modern Cyrillic alphabet:



Download the plugin.


This might cause infinite request loops on certain server configurations and bring down the server process, not recommended to use this plugin.

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