Automatic highlighting of characters from another language in the text

When someone uses a Russian and English layout while writing a text, in some cases this can lead to the fact that, for example, Russian letters of the text appear in English letters. Since the appearance of some letters in English and Russian intersects, this may go unnoticed.

I wrote a small web page where you can type (or paste) text, and choose which language it is in - Russian or English. The page immediately highlights the characters of the English language, if the text is Russian, and, conversely, the characters of the Russian language, if the text is in English.


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Obvious entertainment (not claiming, however, the practical value) - check texts written by different people. Depending on how attentive the author was, the selection will be more or less common in Russian words (where English letters may be present).

Practical application may be, for example, if there is some kind of authorization code, and there is a suspicion that some of the characters in it may be in Russian (and therefore the code does not work). This web page, respectively, allows you to check whether this is so.