HT Script allows you to Insert Headers and Footers Code, insert Google Analytics, Facebook Pixel, custom CSS, custom HTML, jаvascript code to your website header and footer without modifying your theme code. This plugin has the option to add any custom code to your theme in header/footer, no need to edit the theme code. It will save your time and remove the hassle for the theme update.

Demo: https://codecanyon.net/item/ht-script-pro-insert-headers-and-footers-code/24099389