http.headers.Range - document when it's supported for blob URLs

[Josh-Cena]

What type of issue is this?

Missing compatibility data

What information was incorrect, unhelpful, or incomplete?

See mdn/content#24625. This is supported in FF 118; it works in the latest versions of Chrome/Safari, but not sure since when.

What browsers does this problem apply to, if applicable?

No response

What did you expect to see?

A new subfeature about using it with blob:

Did you test this? If so, how?

const blob = new Blob(["Hello, world!"], { type: "text/plain" });
const url = URL.createObjectURL(blob);
fetch(url, {
  headers: {
    Range: "bytes=7-11",
  },
})
  .then((response) => response.text())
  .then((text) => console.log(text)); // "world"

Can you link to any release notes, bugs, pull requests, or MDN pages related to this?

Implementation bugs linked in whatwg/fetch#1520

Do you have anything more you want to share?

No response

MDN URL

https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/Range

MDN metadata

MDN page report details

• Query: http.headers.Range
• Report started: 2025-09-10T19:25:55.630Z

[caugner]

According to https://developer.mozilla.org/en-US/docs/Web/API/Window/fetch#browser_compatibility, Chrome 48 and Safari 10.1 added support for fetch() with blob:. I verified with this JSBin that both Chrome 48 and Safari 10.1 already supported Range with blob:.

Given that this is part of the fetch spec, it probably makes sense to document it there, next to or inside of blob_data_support.