Are there any good examples for "pre-warming" particles systems for Godot 4?

I am trying to build out a little HTML5 project with Godot 4. The issue now is particle systems have a very bad slow down the first time they are initiated. Do I load all the particle systems in the scene that uses them with some type of loading screen? Or can I potentially start loading them in the background on simple UI screens before? The first 4-5 scenes are just UI scenes, so it would be neat if I could potentially load them beforehand. Not sure what type of classes or patterns people use to solve for this.

Could another clean way be to just create a "loading" scene that only has the job of instantiating all the particle systems? That could maybe make it more modular.

If you "pre-warm" everything at once the browser might freeze or crash due to lack of memory if you have a lot of particles and VFX made. I would do something Rust does when entering a game, theres an loading screen that loads each prefab/vfx/etc. separately in the background with a counter (progress bar). Load them in separate thread so that the game doesn't freeze.

Implementing this should be fairly easy, start by accessing the folder(s) all .tscn files are located, this could be like a dictionary with paths and iterate over them instanciating each one and incrementing the progress after it exits the tree.
You can hide all of this under some UI.