To make the question short, I was playing with the dom, I created a text-area and noticed that an element tagged lt-mirror was generated whenever the user type something. The new element is placed just before the text-area. Couldn't find any documentation about it across the web ?
The lt-mirror tag was generated by an extension called LanguageTool, which target the text-areas and check for writing errors.
Did some research about this and found something! Okay, so the person who wrote this probably did something called custom elements. Rather than having nested, verbose elements for a page feature, you could use a custom element to make it more comprehensive and most importantly reusable!
You can create a custom element made with your classes, own methods, and properties, etc, and use it with the built-in HTML elements.
You can find more info on it here:
https://javascript.info/custom-elements
https://developer.mozilla.org/en-US/docs/Web/Web_Components/Using_custom_elements
https://developers.google.com/web/fundamentals/web-components/customelements
