// from https://github.com/mdn/webextensions-examples/blob/master/http-response/background.js

console.log("1");
function listener(details) {

  //console.log("2")
  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});
    //console.log("3");
    str = str.replace( /edc240/g,  '9440ef' );
    str = str.replace( /afd8f8/g,  '4da74f' );
    str = str.replace( /4da74d/g,  'afd8f9' );
    str = str.replace( /9440ed/g,  'edc241' );
    filter.write(encoder.encode(str));
    filter.disconnect();
  }

  return {};
}

try {
  browser.webRequest.onBeforeRequest.addListener(
    listener,
    {urls: ["https://prometheus.cyberia.club/*"], types: ["script"]},
    ["blocking"]
  );
} catch (ex) {
  console.log(ex)
}