Preload on-demand JavaScript

[nisbet-hubbard]

Prerequisites

• I have searched for similar features requests in both open and closed tickets and cannot find a duplicate.
• The feature is still missing in the latest stable version of Elementor ( Elementor Pro )

What problem is your feature request going to solve? Please describe.

Currently, the Improved Asset Loading experiment defers loading certain scripts until user interaction. The js for a pop-up, for example, is only downloaded when the widget gets triggered.

This causes a delay, especially on slower network connections, during which any functionality within the widget in question is unusable. A form widget with steps within a pop-up will for a moment display the final step, for instance, before reverting to the first step when the script is fully loaded.

Describe the solution you'd like

It would be nice if certain well-chosen user actions could trigger on-demand JavaScripts being preloaded, a version of which is suggested by @malchata in his responsible JavaScript book:

function injectPreload (href, module, as) {
			  let preloadHint = document.createElement("link");
			  preloadHint.rel = module ? "modulepreload" : "preload";
			  preloadHint.href = href;
			  if (!module && typeof as !== "undefined") {
			    preloadHint.as = as;
			  }
			  document.head.appendChild(preloadHint);
			}

const inputs = Array.from(document.querySelectorAll("#contact-form input, .contact-form textarea"));
			let preloaded = false;
			inputs.forEach(input => {
			  input.addEventListener("focus", () => {
			    if (!preloaded) {
			      injectPreload("/js/contact-form-validation.js", false, "script");
			      preloaded = true;
			    }
			  }, {
			    once: true
			  })
			});

Describe alternatives you've considered

The alternative is to turn off the experiment and defer js loading using a plugin (ie no longer on-demand).

Additional context

No response