How to upload all the pictures to the site, and only then allow actions?

Question

React

Hello.
How to achieve such an effect that when a user visits a page, a spinner or preloader is first displayed, all images are loaded into the browser's memory, and only then this spinner is removed and all content is displayed?
The content is interactive, and not all pictures are in the markup initially in tags, different pictures appear depending on the user's actions. But, when a user performs a certain action, and a certain picture is displayed to him, it is loaded slowly and not beautifully. Therefore, I want all the pictures to be loaded when the site is opened and immediately at the moment they are displayed, they instantly flash in full size and beauty.
If there is some feature, I would like to know how to achieve this in react, but in native JS, I think it will do too!

Answer 1

onload._ event.