how to change response header in Chrome

Question

I'm dealing with some mp3 link on the internet.

When using Chrome developer tool, I see some have response header with Content-Type:application/octet-stream (links like these force Chrome to download), some links have reponse header with Content-Type:audio/mpeg (links like these allow Chrome to play them streamingly).

Are there any Chrome extensions that allow changing response header? Because I want to change Content-Type

Answer 1

See the Chrome developer page.

Here's a simple example that modifies Content-Type of https://www.google.com/ to text/plain.

chrome.webRequest.onHeadersReceived.addListener(details => {
    let header = details.responseHeaders.find(e => e.name.toLowerCase() === 'content-type') ;
    header.value = 'text/plain';
    return {responseHeaders: details.responseHeaders};
}, {urls: ['https://www.google.com/']}, ['blocking', 'responseHeaders']);

Note that you have to declare both webRequest and webRequestBlocking permissions in manifest.json.