Cross-Origin Resource Sharing (CORS)

CORS is a mechanism that browsers use to control
how one site accesses the resources of another site.
It is designed such that, by default, one web-site
is not allowed to make HTTP requests to another site
using XHR or fetch.
This prevents scripts on another site from acting on behalf
of the user and from gaining access to another
site’s resources without permission.

When using <img>, <picture>, or <canvas>,
the browser automatically blocks access to pixels
when it knows that an image is coming from another site
and the CORS policy disallows access to data.

WebGL requires access to the image data in order
to be able to render the image. Therefore,
images to be rendered using WebGL must only come from servers
that have a CORS policy configured to work with
the domain that serves your application.

Flutter renderers on the web

Flutter offers a choice of two renderers on the web: