I know that this question can be closed because it is based on opinions but, in order to maintain good practices, it follows the following scenario:
1- User has made a registration on the site.
2- Display a feedback message and hide the message element after 5 seconds.
Doubt is, would it be okay to remove the element and insert only when needed or leave it on the page and just do a toggle to show and hide?
Example of how I use it today:
<span style="display:none"> Exemplo feedback </span>
Enhancing : The most semantic would be to hide and show the element using display or use Jquery to add and remove it?