TypeError: invalid media type

[mpardalos]

Describe the bug

I am receiving the following error when receiving a specific request from this service (https://sparkles.sploot.com) to a function running with netlify dev

Netlify crashes before any of my code runs, so I cannot see what the request that causes this looks like.

TypeError: invalid media type
    at Object.parse (/home/mpardalos/Documents/mpardalos.com/node_modules/netlify-cli/node_mod
ules/content-type/index.js:126:11)
    at serveRedirect (file:///home/mpardalos/Documents/mpardalos.com/node_modules/netlify-cli/
dist/utils/proxy.js:323:62)

  System:
    OS: Linux 6.13 Fedora Linux 41 (KDE Plasma)
    CPU: (8) x64 11th Gen Intel(R) Core(TM) i5-1145G7 @ 2.60GHz
  Binaries:
    Node: 22.14.0 - /usr/bin/node
    npm: 10.9.2 - /usr/bin/npm
  npmGlobalPackages:
    netlify-cli: 19.0.2

Steps to reproduce

Reproducing requires being able to use https://sparkles.sploot.com/login, which requires a site set up for indieauth and micropub. If required, I can try to provide an example with my code.

Configuration

[build]
publish = "public"
command = "hugo --minify"

[build.environment]
HUGO_VERSION = "0.111.3"

[context.deploy-preview]
command = "hugo --minify --buildFuture -b $DEPLOY_PRIME_URL"

[[redirects]]
from = "/micropub"
to = "/.netlify/functions/micropub"
status = 200

[dev]
framework = "hugo"

Environment

System:
OS: Linux 6.13 Fedora Linux 41 (KDE Plasma)
CPU: (8) x64 11th Gen Intel(R) Core(TM) i5-1145G7 @ 2.60GHz
Memory: 6.94 GB / 15.34 GB
Container: Yes
Shell: 5.2.32 - /bin/bash
Binaries:
Node: 22.14.0 - /usr/bin/node
npm: 10.9.2 - /usr/bin/npm
npmPackages:
netlify-cli: ^18.1.0 => 18.1.0
npmGlobalPackages:
netlify-cli: 19.0.2

[mpardalos]

Looks like this issue only appears when using a redirect in netlify.toml. Sending a request with Content-Type set to "unknown" triggers this error.

I have worked around this by using the netlify function url (/.netlify/functions/micropub) directly, without using a redirect.