twemoji + Stimulus.js

application.html.haml

!!!
%html
  %head
    %meta{:content => "text/html; charset=UTF-8", "http-equiv" => "Content-Type"}/
    %title Idone.today
    = csrf_meta_tags
    = csp_meta_tag
    = stylesheet_pack_tag 'application', media: 'all', 'data-turbolinks-track': 'reload'
    = javascript_pack_tag 'application', 'data-turbolinks-track': 'reload'
  %body.bg-gray{ data: { controller: 'emoji-parser'} }
    = render 'layouts/header'
    .container-lg.clearfix.p-2
      = render 'layouts/messages'
      = yield

emoji_parser_controller.js

import { Controller } from 'stimulus'
import twemoji from 'twemoji'

export default class extends Controller {
  connect() {
    twemoji.parse(this.element, { folder: 'svg', ext: '.svg'})
  }
}