demo · v146
Roundtrip tester
Type a data URL, fetch it, read the resulting Blob / Response's Content-Type back. Before Chrome 146, parameters after the MIME type (charset, boundary, custom keys) were dropped. From 146 on, they roundtrip cleanly.
This is the tightest possible regression test for the new behaviour: encode → fetch → decode → compare the type string before and after. Anything that survived the roundtrip is a parameter Chrome now preserves.
—
Sent
- type:
- —
- params:
- —
- body bytes:
- —
Roundtripped
- blob.type:
- —
- params:
- —
- body bytes:
- —
Run a roundtrip to see the result.
const dataUrl = "data:" + mime + ";base64," + btoa(body);
const res = await fetch(dataUrl);
const blob = await res.blob();
// 146+ preserves parameters: blob.type === mime
// pre-146: parameters were dropped on the floor