easy-going-rails/app/views/layouts/_notification.html.erb

<% if flash.count.positive? %>
  <script data-turbo-temporary>
    document.addEventListener('turbo:load',(e)=>{

      const common={
        gravity: 'top',
        position: 'center',
        duration: 4000,
        offset: { y: '1em' },
        close: true
      }
      const notice={ className: 'toastify-notice text-black', ...common }
      const alert={ className: 'text-black toastify-alert', ...common }

      <% if flash.notice%>
        Toastify({ text: '<%=flash.notice%>', ...notice}).showToast();
      <%end%>

      <% if flash.alert%>
        Toastify({ text: '<%=flash.alert%>', ...alert}).showToast();
      <%end%>

      // useful to prevent flickering from turbo preview
      Turbo.cache.exemptPageFromPreview()

    }, {once: true})
  </script>
<%end%>