TypeError: fetch failed when fetching with a Request object

[PoneyClairDeLune]

When running Mint with Node.js (undici), fetch always fails when BACKENDS environment variable is set (fetch is invoked with a Request object).

Error stack with ./shx build && ./shx nodeTest:

TypeError: fetch failed
TypeError: fetch failed
    at Object.fetch (node:internal/deps/undici/undici:14374:11)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async z (./dist/node.js:3:8256)
    at async Server. (./dist/node.js:4:1355)

fetch invoked at: src/core/index.js

Node.js compatibility at: src/node/prefix.js, src/node/index.js

Screenshot: