404 when statically serving index.html

[mmkal]

Hi, slightly strange one here. I'm finding that when I serve the output directory (in case it's relevant, via a next.js middleware which streams the file content in from blob storage), visiting <base-path>/index.html doesn't work (I get a pretty 404 page), but visiting <base-path>/ does work, after redirecting to /configs.

Example:

Works: https://www.artifact.ci/artifact/blob/mmkal/artifact.ci/10686862160/eslint/.eslint-config-inspector
404s: https://www.artifact.ci/artifact/blob/mmkal/artifact.ci/10686862160/eslint/.eslint-config-inspector/index.html

Note that clicking "Go back home" on the 404 page makes it work again.

But when you curl each of the above, they are identical. Have I done something wrong in my server or is there some strange client-side logic happening?