The document provides a comprehensive overview of web browser extension development, detailing the technologies involved such as HTML, CSS, and JavaScript. It outlines the structure and components necessary for creating extensions for both Firefox and Google Chrome, including specific file formats like install.rdf and manifest.json. Additionally, it includes links for publishing extensions on respective browser stores and a bibliography for further reading.

1. Web browser extension development Chisan Petrisor Laurentiu Stefanache Pavel Cosmin

2. What is a browser extension?

3. A browser extension is a computer program that extends the functionality of a web browser in some way.

4. Technologies used for browser extension development HTML CSS Javascript XML based languages HTML5 API ..and many other technologies

5. Structure of an Extension metadata information user interface extension functionality

6. Developing firefox extensions

7. Web Developer AdBlock Plus Firebug Delicious

8. Folder structure /chrome content locale skin install.rdf chrome.manifest file.xul file.js file.dtd file.properties file.css

9. Everything zipped in an .xpi file extention.xpi

10. <?xml version=&quot;1.0&quot;?> <RDF xmlns=&quot;http://www.w3.org/1999/02/22-rdf-syntax-ns#&quot; xmlns:em=&quot;http://www.mozilla.org/2004/em-rdf#&quot;> <Description about=&quot;urn:mozilla:install-manifest&quot;> <em:id>helloworld@xulschool.com</em:id> <em:name>XUL School Hello World</em:name> <em:description>Welcome to XUL School!</em:description> <em:version>0.1</em:version> <em:creator>Appcoast</em:creator> <em:homepageURL>https://developer.mozilla.org/en/XUL_School</em:homepageURL> <em:type>2</em:type> <!-- Mozilla Firefox --> <em:targetApplication> <Description> <em:id>{ec8030f7-c20a-464f-9b0e-13a3a9e97384}</em:id> <em:minVersion>3.0</em:minVersion> <em:maxVersion>4.0</em:maxVersion> </Description> </em:targetApplication> </Description> </RDF> install.rdf (metadata) Extension files Extension folder

11. <Description about=&quot;urn:mozilla:install-manifest&quot;> <em:id> [email_address] </em:id> <em:name>XUL School Hello World</em:name> <em:description>Welcome to XUL School!</em:description> <em:version>0.1</em:version> <em:creator>Appcoast</em:creator> <em:homepageURL> https://developer.mozilla.org/en/XUL_School </em:homepageURL> <em:type>2</em:type> … </Description> install.rdf (metadata) Extension files Extension folder

12. <Description about=&quot;urn:mozilla:install-manifest&quot;> ... <!-- Mozilla Firefox --> <em:targetApplication> <Description> <em:id> {ec8030f7-c20a-464f-9b0e-13a3a9e97384} </em:id> <em:minVersion>3.0</em:minVersion> <em:maxVersion>4.0</em:maxVersion> </Description> </em:targetApplication> </Description> install.rdf (metadata) Extension files Extension folder

13. content xulschoolhello jar:chrome/xulschoolhello.jar!/content/ skin xulschoolhello classic/1.0 jar:chrome/xulschoolhello.jar!/skin/ locale xulschoolhello en-US jar:chrome/xulschoolhello.jar!/locale/en-US/ overlay chrome://browser/content/browser.xul chrome://xulschoolhello/content/browserOverlay.xul chrome.maifest (file references) Extension files Extension folder Extension files Extension folder

14. <?xml version=&quot;1.0&quot;?> <?xml-stylesheet type=&quot;text/css&quot; href=&quot;chrome://global/skin/&quot; ?> <?xml-stylesheet type=&quot;text/css&quot; href=&quot;chrome://xulschoolhello/skin/browserOverlay.css&quot; ?> <!DOCTYPE overlay SYSTEM &quot;chrome://xulschoolhello/locale/browserOverlay.dtd&quot;> <overlay id=&quot;xulschoolhello-browser-overlay&quot; xmlns=&quot;http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul&quot;> <script type=&quot;application/x-javascript&quot; src=&quot;chrome://xulschoolhello/content/browserOverlay.js&quot; /> <stringbundleset id=&quot;stringbundleset&quot;> <stringbundle id=&quot;xulschoolhello-string-bundle&quot; src=&quot;chrome://xulschoolhello/locale/browserOverlay.properties&quot; /> </stringbundleset> <menupopup id=&quot;menu_ToolsPopup&quot;> <menu id=&quot;xulschoolhello-hello-menu&quot; label=&quot;&xulschoolhello.hello.label;&quot; accesskey=&quot;&xulschoolhello.helloMenu.accesskey;&quot; insertafter=&quot;javascriptConsole,devToolsSeparator&quot;> <menupopup> <menuitem id=&quot;xulschoolhello-hello-menu-item&quot; label=&quot;&xulschoolhello.hello.label;&quot; accesskey=&quot;&xulschoolhello.helloItem.accesskey;&quot; oncommand=&quot;XULSchoolChrome.BrowserOverlay.sayHello(event);&quot; /> </menupopup> </menu> </menupopup> </overlay> browserOverlay.xul Extension files content folder

15. Extension files Content folder Extension files Content folder Extension files content folder <overlay id=&quot;xulschoolhello-browser-overlay&quot; xmlns=&quot;http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul&quot;> browserOverlay.xul

16. browserOverlay.xul <script type=&quot;application/x-javascript&quot; src=&quot;chrome://xulschoolhello/content/ browserOverlay.js&quot; /> Extension files content folder

17. <menupopup id=&quot;menu_ToolsPopup&quot;> <menu id=&quot;xulschoolhello-hello-menu&quot; label=&quot;&xulschoolhello.hello.label;&quot; accesskey=&quot;&xulschoolhello.helloMenu.accesskey;&quot; insertafter=&quot;javascriptConsole,devToolsSeparator&quot;> <menupopup> <menuitem id=&quot;xulschoolhello-hello-menu-item&quot; label=&quot;&xulschoolhello.hello.label;&quot; accesskey=&quot;&xulschoolhello.helloItem.accesskey;&quot; oncommand=&quot;XULSchoolChrome.BrowserOverlay.sayHello(event);&quot; /> </menupopup> </menu> </menupopup> browserOverlay.xul Extension files content folder

18. /** * XULSchoolChrome namespace. */ if (&quot;undefined&quot; == typeof(XULSchoolChrome)) { var XULSchoolChrome = {}; }; /** * Controls the browser overlay for the Hello World extension. */ XULSchoolChrome.BrowserOverlay = { /** * Says 'Hello' to the user. */ sayHello : function(aEvent) { let stringBundle = document.getElementById(&quot;xulschoolhello-string-bundle&quot;); let message = stringBundle.getString(&quot;xulschoolhello.greeting.label&quot;); window.alert(message); } }; browserOverlay.js Extension files content folder

19. browserOverlay.dtd <!ENTITY xulschoolhello.hello.label &quot;Hello World &quot;> <!ENTITY xulschoolhello.helloMenu.accesskey &quot;l&quot;> <!ENTITY xulschoolhello.helloItem.accesskey &quot;H&quot;> Extension files locale folder

20. browserOverlay.properties xulschoolhello.greeting.label = Hello! Extension files locale folder

21. Extension files skin folder Here we put the CSS file for styling the the xul file

22. Tools for development Komodo Edit Web developer DOM Inspector JavaScript Debugger

23. Developing google chrome extension

24. Folder structure / manifest.json popup.html file_name.js * Any file* * optional files

25. Now, let's see a simple exemple

26. { &quot;name&quot;: &quot;My First Extension&quot;, &quot;version&quot;: &quot;1.0&quot;, &quot;description&quot;: &quot;The first extension that I made.&quot;, &quot;browser_action&quot;: { &quot;default_icon&quot;: &quot;icon.png&quot;, &quot;popup&quot; : &quot;popup.html&quot; }, &quot;permissions&quot;: [ &quot;http://api.flickr.com/&quot; ] } manifest.json

27. <style> body { min-width:357px; overflow-x:hidden; } img { margin:5px; border:2px solid black; vertical-align:middle; width:75px; height:75px; } </style> ... popup.html

28. <script> var req = new XMLHttpRequest(); req.open( &quot;GET&quot;, &quot;http://api.flickr.com/services/rest/?&quot; + &quot;method=flickr.photos.search&&quot; + &quot;api_key=90485e931f687a9b9c2a66bf58a3861a&&quot; + &quot;text=hello%20world&&quot; + &quot;safe_search=1&&quot; + // 1 is &quot;safe&quot; &quot;content_type=1&&quot; + // 1 is &quot;photos only&quot; &quot;sort=relevance&&quot; + // another good one is &quot;interestingness-desc&quot; &quot;per_page=20&quot;, true); req.onload = showPhotos; req.send(null); … </script> popup.html

29. <script> ... function showPhotos() { var photos = req.responseXML.getElementsByTagName(&quot;photo&quot;); for (var i = 0, photo; photo = photos[i]; i++) { var img = document.createElement(&quot;image&quot;); img.src = constructImageURL(photo); document.body.appendChild(img); } } // See: http://www.flickr.com/services/api/misc.urls.html function constructImageURL(photo) { return &quot;http://farm&quot; + photo.getAttribute(&quot;farm&quot;) + &quot;.static.flickr.com/&quot; + photo.getAttribute(&quot;server&quot;) + &quot;/&quot; + photo.getAttribute(&quot;id&quot;) + &quot;_&quot; + photo.getAttribute(&quot;secret&quot;) + &quot;_s.jpg&quot;; } </script> popup.html

30. We can load our extension uppacked or zipped in a .crx file manifes.json .js .html .css .png CRX

31. And what's next ?

32. Publish your firefox extension https://addons.mozilla.org/en-US/firefox/extensions/

33. Publish your chrome extension https://chrome.google.com/extensions/developer/dashboard

34. Bibliography http://code.google.com/chrome/extensions/getstarted.html https://developer.mozilla.org/en/Building_an_Extension