Request signature we calculated does not match (bis) [chunked-upload]

Same as these (which, sadly, were automatically closed before obtaining an answer):

After further investigation we found that “small files” (under the 100 MB) upload successfully.
But as soon as a file needs chunking we starting getting the AWS upload error.

@charles ? (Pretty sure it’s a common and easily reproducible [still, very annoying] bug)

Hi Raf,
can you tell (again?) more about your proxy. This is 99% of the time an issue with the request Host header being carried out through a proxy.

No proxy (except Cloudflare). It’s all within cells Go binary (including SSL), no Apache nor Nginx nor docker involved.
(Is there a ./cells command to dump the internal httpd configuration if that’s of any use for you?)