Firefox users can add functionality to their browser by installing an add-on. To install an add-n click on Tools->Add-ons.
You can then search for your requested add-on: add-on to download movies from a site, to share a page in Facebook, to add a Delicious bookmark, etc. Another useful add-on is DOM Inspector, which allows you to locate and modify document elements. Firefox add-ons are written in Javascript and access document elements, just like Javascript scripts within HTML documents, except that the document an add-on accesses is named Chrome Document.
Accessing the Chrome Document
The Chrome document contains more than just the “window” element, accessed from a web page using Javascript. Chrome also contains menus, toolbars and other widgets. Let’s make changing one of the Chrome document’s elements your first step in add-on development. If you don’t have DOM Inspector installed in your browser, you can get it here. Now, you can use it to play around a little bit. For example, let’s change the ‘Tools’ menu’s name to ‘Fools’.
To do so, perform the following steps:
- Tools->Web Developer->DOM Inspector:
- In the DOM Inspector menu bar, choose: File->Inspect Chrome Document->(tab name)
- In the DOM Inspector Window, click the magnifying-glass icon.
- In the browser’s window click ‘Tools’ menu
IMPORTANT! This will NOT work if the “Global Menu BAR Integration” add-on is enabled!!! - Open the DOM Inspector window.
The ‘tools-menu’ node will appear on the right-hand part of the window.
Now, you can see that the value of the node’s “label” attribute is “Tools” - Right click the “Label” attribute, then left-click “Edit”.
- In the “Edit Attributes” window opened change the Node Value and click “OK”.
- Nice work!!!
Congratulations! Now you know how to access chrome elements and modify them. This will help you later when you learn how to do it in Javascript.
Learn more about add-on development here.
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