CORS with georaster/georaster-for-leaflet

I'm trying to read images from S3 with georaster/georaster-for-leaflet. If I disable all security, such as:

`chromium --disable-web-security --user-data-dir=/tmp/chromium`

...images load as expected. However, under normal browser start up I constantly get a CORS error message:

`Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://longurl/some.tif. (Reason: CORS header ‘Access-Control-Allow-Origin’ missing). Status code: 206.`

I'm not sure what parameters to pass or how to pass them to georaster. Any help would be greatly appreciated!

Start by checking how georaster and georaster-for-leaflet request the S3 GeoTIFF and handle the browser's partial-content response. Reproduce the request with normal browser security and compare it with the provided Chromium command. Done means identifying whether the required CORS behavior belongs in the library or the S3 configuration and documenting the supported path.

Written by the indexing model from the issue text.