Slow Startup in Web if spawning PbrBundle

[mineichen]

I currently use Bevy to render a live Pointcloud from a Ouster Lidar sensor. It works great! I adapted the instancing example to Display a 200'000 pointcloud with 20Hz in the browser (webgl2) or as a native App (Metal), where each Point is Displayed as an instances Box-Mesh. The startup time is around 1s, great!

If i add a simple

commands.spawn(PbrBundle {
        mesh: meshes.add(Plane3d::default().mesh().size(5.0, 5.0)),
        material: materials.add(Color::rgb(0.3, 0.5, 0.3)),
        ..default()
    });

to my setup-function, the Startup-Time becomes very slow. It goes from 1s to around 13s. Just adding the StandardMaterial doesn't affect performance. Building a Native App for OSX/Metal is still as fast as before. I guess that adding a PbrBundle triggers some big systems in the background. After waiting, the Console is showing the following two Warnings. Could they be related to the slow loading times?

WebGL warning: drawElementsInstanced: Depth texture comparison requests (e.g. LINEAR) Filtering, but behavior is implementation-defined, and so on some systems will sometimes behave as NEAREST. (warns once)
WebGL warning: drawArraysInstanced: Drawing without vertex attrib 0 array enabled forces the browser to do expensive emulation work when running on desktop OpenGL platforms, for example on Mac. It is preferable to always draw with vertex attrib 0 array enabled, by using bindAttribLocation to bind some always-used attribute to location 0.

I considered adding a custom Shader to avoid Spawning the PbrBundle, but I don't want to fight the Bevy way of doing things. Waiting 13s unfortunately is not an option. I don't need all the lighting stuff right now. Is there a way to disable some of the heavy systems i don't need (I currently load all DefaultPlugins)? I'm also curious why instancing works with the Cube, even if the Heavy-Systems are not up and running...