CODE EXAMPLE FOR JAVASCRIPT

jquery select first matching element

// Selects the first matched DOM element.
let myElem = jQuery('.elemClass:first');

/*
	Some notes:
    
    - Because :first is a jQuery extension and not part 
    of the CSS specification, queries using :first cannot 
    take advantage of the performance boost provided by the 
    native DOM querySelectorAll() method. To achieve the 
    best performance when using :first to select elements, 
    first select the elements using a pure CSS selector, 
    then use .filter(":first").
    
	- Selected elements are in the order of their appearance 
    in the document.
*/