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+<!--
+ Copyright 2016 Soren Stoutner <soren@stoutner.com>.
+
+ This file is part of Privacy Browser <https://www.stoutner.com/privacy-browser>.
+
+ Privacy Browser is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Privacy Browser is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with Privacy Browser. If not, see <http://www.gnu.org/licenses/>. -->
+
+<html>
+<head>
+<!-- We have to make an image into its own block to center it. -->
+<style>
+ h3 {
+ color: 0D4781;
+ }
+
+ img.center {
+ display: block;
+ margin-left: auto;
+ margin-right: auto;
+ }
+</style>
+</head>
+
+<body>
+<h3>Browser Identification</h3>
+
+<p>When web browsers connect to websites, they send a user agent, which identifies the browser and the
+ rendering capabilities it possesses. They website can use this information to decide which version of the
+ website to send to the browser. For example, many websites have different versions for desktop and
+ mobile browsers.</p>
+
+<p>By default, Privacy Browser uses the built-in user agent that comes with the WebView installed on the
+ device. You can see what it is by going to the <strong>Settings</strong> screen and setting the <strong>User
+ agent</strong> to <strong>WebView Default</strong>. The screenshot below shows a Nexus 6P running Android 6.0.1
+ with Android System WebView 51.0.2704.81 installed.</p>
+
+<img class="center" src="../en/images/user_agent.png" height="640" width="360">
+
+<p>There is enough information in the user agent that sometimes only a few visitors to a website will be the same. If the user agent
+ is combined with another piece of non-unique identifying information, often it results in a unique fingerprint.
+ The Electronic Frontier Foundation created a tool called <a href="https://panopticlick.eff.org/">Panopticlick</a>
+ to demonstrate how much information can be gleaned from these sources. If this test is run with JavaScript enabled the
+ amount of information that is disclosed increases greatly. <a href="https://www.browserleaks.com">Browser Leaks</a> and
+ <a href="https://amiunique.org/">Am I Unique</a> are also good sources of information.</p>
+
+<img class="center" src="../en/images/panopticlick.png" height=640" width="360">
+
+<p>Privacy Browser allows you to change the user agent. There are several preset options that match common browsers and operating systems.
+ Privacy Browser also has its own user agent, which is simply PrivacyBrowser/1.0. For tracking purposes, anything that is rare is easier
+ to track. If Privacy Browser becomes common and many people use PrivacyBrowser/1.0 as their user agent, it will be a good choice for privacy.
+ For now, choosing something that has lots of hits on a web server, like <strong>Edge 13 on Windows 10</strong>, allows the device to
+ blend in with the crowd. Firefox or Chrome provide less privacy because they auto-update and their version numbers change so quickly
+ that it is likely the user agents included in Privacy Browser will often be out of step with the majority of user agents in the
+ server logs.</p>
+
+<p>A second reason to change the user agent is to convince the web server to send the desktop version of the web page, which often works
+ better on modern smart phones than the mobile version. For this purpose, PrivacyBrowser/1.0 works well, because web servers typically
+ default to the desktop version unless they recognize a phone browser agent.</p>
+
+<p>Android's WebView does not allow the user agent to be blank. If it is, WebView simply sends the default user-agent to the server.</p>
+</body>
+</html>
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