Controlling a Firefox Extension via Javascript

Question

Is it possible, using javascript, to control an overlay firefox extension? I've extracted the contents of the extension and have identified what functions/methods I need to run, but they are not accessible within the scope of the console.

Thanks in advance for any ideas.

Answer 1

Yes it possible to interact with other add-ons, given the right circumstances.

My test case here will be com.googlecode.sqlitemanager.openInOwnWindow(), which is part of the SqliteManager addon.

1. In newer builds (I'm using Nightly), there is the Browser Toolbox. With it is is as simple as opening a toolbox and executing com.googlecode.sqlitemanager.openInOwnWindow() in the Console.

2. You may instead use the Browser Console (or any chrome enabled WebDev Console for that matter, e.g. the Console of "about:newtab"). But you need some boilerplate code to first find the browser window. So here is the code you can execute there: var bwin = Services.wm.getMostRecentWindow("navigator:browser"); bwin.com.googlecode.sqlitemanager.openInOwnWindow()

3. Again, enable chrome debugging. Then open a Scratchpad and switch to Chrome in the Environment menu. Now executing com.googlecode.sqlitemanager.openInOwnWindow() in our Scratchpad will work.

4. You may of course write your own overlay add-on.

5. As a last resort, patch the add-on itself.

6. Bootstrapped/SDK add-ons: you can load XPIProvider.jsm (which changed location recently) and get to the bootstrapped scope (run environment of bootstrap.js) via XPIProvider.bootstrapScopes[addonID], and take it from there (use whatever is in the bootstrap scope, e.g. the SDK loader).

Now about the right circumstances: If and how you can interact with a certain add-on depends on the add-on. Add-ons may have global symbols in their overlay and hence browser window, such as in the example I used. Or may use (to some extend) JS code modules. Or have their own custom loader stuff (e.g. AdBlock Plus has their own require()-like stuff and SDK add-ons have their own loader, which isn't exactly easy to infiltate)...

Since your question is rather unspecific, I'll leave it at this.

Edit by question asker: This is correct, however I figured I'd add an example of the code I ended up using in the end, which was in fact taken directly from mozilla's developer network website:

In my chrome js:

var myExtension = {
  myListener: function(evt) {
   IprPreferences.setFreshIpStatus(true); // replace with whatever you want to 'fire' in the extension
  }
}

document.addEventListener("MyExtensionEvent", function(e) { myExtension.myListener(e); }, false, true);
// The last value is a Mozilla-specific value to indicate untrusted content is allowed to trigger the event.

In the web content:

var element = document.createElement("MyExtensionDataElement");
element.setAttribute("attribute1", "foobar");
element.setAttribute("attribute2", "hello world");
document.documentElement.appendChild(element);

var evt = document.createEvent("Events");
evt.initEvent("MyExtensionEvent", true, false);
element.dispatchEvent(evt);