I have a WordPress website. In that I am using smsAlert plugin. My question is not especial to that plugin, but is more related to JS and HTML and character encoding. I want that the error messages in this form in my website be in Persian language. So I changed the “invalid number” message and “please provide …” messages in the source file (phone-number-validate.js) in my host. But when I see in the browser, the source file does not recognize my Persian characters. Instead it substitute that with some unknow chars. This is the source file in browser link : ( view-source:https://learnblog.hamid-davodi.com/wp-content/plugins/sms-alert/js/phone-number-validate.js?ver=3.7.1 ). Please copy and past all text from “view-source” word in the address bar of your browser to see the problem!

This is the image of unknown characters:

Could any developer please help me why this happens and how could I resolve that?