Blocks fails to load reliably on slow networks

In a school setting with a less than ideal network, it very often takes students several reload attempts before code.world/blocks will load for them. Not sure if this is some kind of race condition, or just a consequence of the size of the generated JavaScript in the `funblocks-client` package.

Whatever the case, this is a serious problem. It not only takes 5 to 10 minutes away from each class session, but far worse, it leaves students feeling like can't use the site without adults there ready to handle the problems.

Reproduce el fallo de carga en code.world/blocks con una red lenta e inspecciona el paquete funblocks-client y su JavaScript generado. Determina si el comportamiento se debe a una condición de carrera o a un problema de tamaño del payload y, a continuación, define un resultado de carga fiable que pueda verificarse en pruebas repetidas con una red lenta.

Escrito por el modelo de indexación a partir del texto del issue.