Signature box (Textarea) limits the number of words and prompts timely_form special effects

When the entered characters reach the limit, no more characters can be entered. If you enter one character, it will be deleted by the program. Is it interesting?

<title>Text box input restrictions</title> <textarea onkeyup='value=value.substr(0,10);this.nextSibling.innerHTML=value.length "/10";'><div>0/10</div>
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