webRequest.StreamFilter.write()

Writes some response data to the output stream.

You can only call this function after the onstart event has fired.

Syntax

filter.write(
  data    // ArrayBuffer or Uint8Array
)

Parameters

data: Uint8Array or ArrayBuffer: array of bytes containing the data to pass to the browser's rendering engine.

Return value

None.

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`write`	No	No	57	?	No	No	?	?	57	?	?	?

Examples

This example uses write(), to replace "Example" in the first chunk of the response with "WebExtension Example".

function listener(details) {
  let filter = browser.webRequest.filterResponseData(details.requestId);
  let decoder = new TextDecoder("utf-8");
  let encoder = new TextEncoder();

  filter.ondata = event => {
    let str = decoder.decode(event.data, {stream: true});
    // Just change any instance of Example in the HTTP response
    // to WebExtension Example.
    str = str.replace(/Example/g, 'WebExtension Example');
    filter.write(encoder.encode(str));
    filter.disconnect();
  }

  //return {}; // not needed
}

browser.webRequest.onBeforeRequest.addListener(
  listener,
  {urls: ["https://example.com/*"], types: ["main_frame"]},
  ["blocking"]
);

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https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/webRequest/StreamFilter/write