Injecting JS into every page ?

[LiEnby]

i noticed theres a bunch of javascript appended to the end of the page its most apparent when viewing XML's (eg: ps4-updatelist.xml)

function(canvas, canvasfont, audioblock, battery, webgl, webrtcdevice, gamepad, webvr, bluetooth, timezone, clientrects, clipboard, browserplugins){
 function processFunctions(scope) {
 /* Browser Plugins */
 if (browserplugins == 'true') {
 scope.Object.defineProperty(navigator, "plugins", {enumerable: true, configurable: true, get: function() {
 var browserplugins_triggerblock = scope.document.createElement('div');
 browserplugins_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_browserplugins';
 browserplugins_triggerblock.title = 'navigator.plugins';
 document.documentElement.appendChild(browserplugins_triggerblock);
 return "";
 }});
 }
 /* Canvas */
 if (canvas != 'false') {
 var fakecanvas = scope.document.createElement('canvas');
 fakecanvas.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_canvas';
 if (canvas == 'random') {
 var fakewidth = fakecanvas.width = Math.floor(Math.random() * 999) + 1;
 var fakeheight = fakecanvas.height = Math.floor(Math.random() * 999) + 1;
 }
 var canvas_a = scope.HTMLCanvasElement;
 var origToDataURL = canvas_a.prototype.toDataURL;
 var origToBlob = canvas_a.prototype.toBlob;
 canvas_a.prototype.toDataURL = function() {
 fakecanvas.title = 'toDataURL';
 document.documentElement.appendChild(fakecanvas);
 if (canvas == 'block') return false;
 else if (canvas == 'blank') {
 fakecanvas.width = this.width;
 fakecanvas.height = this.height;
 return origToDataURL.apply(fakecanvas, arguments);
 } else if (canvas == 'random') {
 return origToDataURL.apply(fakecanvas, arguments);
 }
 };
 canvas_a.prototype.toBlob = function() {
 fakecanvas.title = 'toBlob';
 document.documentElement.appendChild(fakecanvas);
 if (canvas == 'block') return false;
 else if (canvas == 'blank') {
 fakecanvas.width = this.width;
 fakecanvas.height = this.height;
 return origToBlob.apply(fakecanvas, arguments);
 } else if (canvas == 'random') {
 return origToBlob.apply(fakecanvas, arguments);
 }
 };
 var canvas_b = scope.CanvasRenderingContext2D;
 var origGetImageData = canvas_b.prototype.getImageData;
 canvas_b.prototype.getImageData = function() {
 fakecanvas.title = 'getImageData';
 document.documentElement.appendChild(fakecanvas);
 if (canvas == 'block') return false;
 else if (canvas == 'blank') {
 fakecanvas.width = this.width;
 fakecanvas.height = this.height;
 return origGetImageData.apply(fakecanvas.getContext('2d'), arguments);
 } else if (canvas == 'random') {
 return origGetImageData.apply(fakecanvas.getContext('2d'), [Math.floor(Math.random() * fakewidth) + 1, Math.floor(Math.random() * fakeheight) + 1, Math.floor(Math.random() * fakewidth) + 1, Math.floor(Math.random() * fakeheight) + 1]);
 }
 }
 var origGetLineDash = canvas_b.prototype.getLineDash;
 canvas_b.prototype.getLineDash = function() {
 fakecanvas.title = 'getLineDash';
 document.documentElement.appendChild(fakecanvas);
 if (canvas == 'block') return false;
 else if (canvas == 'blank') {
 fakecanvas.width = this.width;
 fakecanvas.height = this.height;
 return origGetLineDash.apply(fakecanvas.getContext('2d'), [0, 0]);
 } else if (canvas == 'random') {
 return origGetLineDash.apply(fakecanvas.getContext('2d'), [Math.floor(Math.random() * fakewidth) + 1, Math.floor(Math.random() * fakeheight) + 1]);
 }
 }
 var canvas_c = scope.WebGLRenderingContext;
 var origReadPixels = canvas_c.prototype.readPixels;
 canvas_c.prototype.readPixels = function() {
 fakecanvas.title = 'readPixels';
 document.documentElement.appendChild(fakecanvas);
 if (canvas == 'block') return false;
 else if (canvas == 'blank') {
 fakecanvas.width = this.width;
 fakecanvas.height = this.height;
 return origReadPixels.apply(fakecanvas.getContext('webgl'), arguments);
 } else if (canvas == 'random') {
 return origReadPixels.apply(fakecanvas.getContext('webgl'), [Math.floor(Math.random() * fakewidth) + 1, Math.floor(Math.random() * fakeheight) + 1, Math.floor(Math.random() * fakewidth) + 1, Math.floor(Math.random() * fakeheight) + 1, arguments[4], arguments[5], arguments[6]]);
 }
 }
 }
 /* Audio Block */
 if (audioblock == 'true') {
 var audioblock_triggerblock = scope.document.createElement('div');
 audioblock_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_audio';
 var audioblock_a = scope.AudioBuffer;
 audioblock_a.prototype.copyFromChannel = function() {
 audioblock_triggerblock.title = 'copyFromChannel';
 document.documentElement.appendChild(audioblock_triggerblock);
 return false;
 }
 audioblock_a.prototype.getChannelData = function() {
 audioblock_triggerblock.title = 'getChannelData';
 document.documentElement.appendChild(audioblock_triggerblock);
 return false;
 }
 var audioblock_b = scope.AnalyserNode;
 audioblock_b.prototype.getFloatFrequencyData = function() {
 audioblock_triggerblock.title = 'getFloatFrequencyData';
 document.documentElement.appendChild(audioblock_triggerblock);
 return false;
 }
 audioblock_b.prototype.getByteFrequencyData = function() {
 audioblock_triggerblock.title = 'getByteFrequencyData';
 document.documentElement.appendChild(audioblock_triggerblock);
 return false;
 }
 audioblock_b.prototype.getFloatTimeDomainData = function() {
 audioblock_triggerblock.title = 'getFloatTimeDomainData';
 document.documentElement.appendChild(audioblock_triggerblock);
 return false;
 }
 audioblock_b.prototype.getByteTimeDomainData = function() {
 audioblock_triggerblock.title = 'getByteTimeDomainData';
 document.documentElement.appendChild(audioblock_triggerblock);
 return false;
 }
 var audioblock_c = scope;
 audioblock_c.AudioContext = function() {
 audioblock_triggerblock.title = 'AudioContext';
 document.documentElement.appendChild(audioblock_triggerblock);
 return false;
 }
 audioblock_c.webkitAudioContext = function() {
 audioblock_triggerblock.title = 'webkitAudioContext';
 document.documentElement.appendChild(audioblock_triggerblock);
 return false;
 }
 }
 /* Canvas Font */
 if (canvasfont == 'true') {
 var canvasfont_triggerblock = scope.document.createElement('div');
 canvasfont_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_canvasfont';
 var canvasfont_a = scope.CanvasRenderingContext2D;
 canvasfont_a.prototype.measureText = function() {
 canvasfont_triggerblock.title = 'measureText';
 document.documentElement.appendChild(canvasfont_triggerblock);
 return false;
 }
 }
 /* Battery */
 if (battery == 'true') {
 var battery_triggerblock = scope.document.createElement('div');
 battery_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_battery';
 var battery_a = scope.navigator;
 battery_a.getBattery = function() {
 battery_triggerblock.title = 'getBattery';
 document.documentElement.appendChild(battery_triggerblock);
 return void(0);
 }
 }
 /* WebGL */
 if (webgl == 'true') {
 var webgl_triggerblock = scope.document.createElement('div');
 webgl_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_webgl';
 var webgl_a = scope.HTMLCanvasElement;
 var origGetContext = webgl_a.prototype.getContext;
 webgl_a.prototype.getContext = function(arg) {
 if (arg.match(/webgl/i)) {
 webgl_triggerblock.title = 'getContext';
 document.documentElement.appendChild(webgl_triggerblock);
 return false;
 }
 return origGetContext.apply(this, arguments);
 }
 }
 /* WebRTC */
 if (webrtcdevice == 'true') {
 var webrtc_triggerblock = scope.document.createElement('div');
 webrtc_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_webrtc';
 var webrtc_a = scope.MediaStreamTrack;
 webrtc_a.getSources = function() {
 webrtc_triggerblock.title = 'getSources';
 document.documentElement.appendChild(webrtc_triggerblock);
 return false;
 }
 webrtc_a.getMediaDevices = function() {
 webrtc_triggerblock.title = 'getMediaDevices';
 document.documentElement.appendChild(webrtc_triggerblock);
 return false;
 }
 var webrtc_b = scope.navigator.mediaDevices;
 webrtc_b.enumerateDevices = function() {
 webrtc_triggerblock.title = 'enumerateDevices';
 document.documentElement.appendChild(webrtc_triggerblock);
 return false;
 }
 }
 /* Gamepad */
 if (gamepad == 'true') {
 var gamepad_triggerblock = scope.document.createElement('div');
 gamepad_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_gamepad';
 var gamepad_a = scope.navigator;
 gamepad_a.getGamepads = function() {
 gamepad_triggerblock.title = 'getGamepads';
 document.documentElement.appendChild(gamepad_triggerblock);
 return false;
 }
 }
 /* WebVR */
 if (webvr == 'true') {
 var webvr_triggerblock = scope.document.createElement('div');
 webvr_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_webvr';
 var webvr_a = scope.navigator;
 webvr_a.getVRDisplays = function() {
 webvr_triggerblock.title = 'getVRDisplays';
 document.documentElement.appendChild(webvr_triggerblock);
 return false;
 }
 }
 /* Bluetooth */
 if (bluetooth == 'true') {
 if (scope.navigator.bluetooth) {
 var bluetooth_triggerblock = scope.document.createElement('div');
 bluetooth_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_bluetooth';
 var bluetooth_a = scope.navigator.bluetooth;
 bluetooth_a.requestDevice = function() {
 bluetooth_triggerblock.title = 'requestDevice';
 document.documentElement.appendChild(bluetooth_triggerblock);
 return false;
 }
 }
 }
 /* Client Rectangles */
 if (clientrects == 'true') {
 var clientrects_triggerblock = scope.document.createElement('div');
 clientrects_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_clientrects';
 Element.prototype.getClientRects = function() {
 clientrects_triggerblock.title = 'getClientRects';
 document.documentElement.appendChild(clientrects_triggerblock);
 return [{'top': 0, 'bottom': 0, 'left': 0, 'right': 0, 'height': 0, 'width': 0}];
 }
 }
 /* Timezone */
 if (timezone != 'false') {
 var timezone_triggerblock = scope.document.createElement('div');
 timezone_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_timezone';
 var timezone_a = scope.Date;
 timezone_a.prototype.getTimezoneOffset = function() {
 timezone_triggerblock.title = 'getTimezoneOffset';
 document.documentElement.appendChild(timezone_triggerblock);
 if (timezone == 'random') return ['720','660','600','570','540','480','420','360','300','240','210','180','120','60','0','-60','-120','-180','-210','-240','-270','-300','-330','-345','-360','-390','-420','-480','-510','-525','-540','-570','-600','-630','-660','-720','-765','-780','-840'][Math.floor(Math.random() * 39)];
 return timezone;
 }
 }
 /* Clipboard */
 if (clipboard == 'true') {
 var clipboard_triggerblock = scope.document.createElement('div');
 clipboard_triggerblock.className = 'scriptsafe_oiigbmnaadbkfbmpbfijlflahbdbdgdf_clipboard';
 var clipboard_a = document;
 var origExecCommand = clipboard_a.execCommand;
 clipboard_a.execCommand = function() {
 clipboard_triggerblock.title = 'execCommand';
 document.documentElement.appendChild(clipboard_triggerblock);
 if (arguments[0] == 'cut' || arguments[0] == 'copy') return false;
 return origExecCommand.apply(this, arguments);
 };
 }
 }
 processFunctions(window);
 var iwin = HTMLIFrameElement.prototype.__lookupGetter__('contentWindow'), idoc = HTMLIFrameElement.prototype.__lookupGetter__('contentDocument');
 Object.defineProperties(HTMLIFrameElement.prototype, {
 contentWindow: {
 get: function() {
 var frame = iwin.apply(this);
 if (this.src && this.src.indexOf('//') != -1 && location.host != this.src.split('/')[2]) return frame;
 try { frame.HTMLCanvasElement } catch (err) { /* do nothing*/ }
 processFunctions(frame);
 return frame;
 }
 },
 contentDocument: {
 get: function() {
 if (this.src && this.src.indexOf('//') != -1 && location.host != this.src.split('/')[2]) return idoc.apply(this);
 var frame = iwin.apply(this);
 try { frame.HTMLCanvasElement } catch (err) { /* do nothing*/ }
 processFunctions(frame);
 return idoc.apply(this);
 }
 }
 });
 })('false','true','false','true','true','true','true','true','true','false','true','true', 'true');

[zireael-0]

This is one of the methods WebExtensions use to extend the web. You can read more about it here.

I don't see an issue in this. You could have at least mentioned what's wrong and what browser you're using.