I have a long time stick with Conkeror as my default web browser and get used to configuring/adding new features to my browser using js code with all the XUL Api through the .conkerorrc file. I'm migrating to Firefox since it has better support and is actively maintained by Mozilla. However, one of the feature that I've been missing so much is the dot file, which I can easily configure anything that I like, back up all of them through git and eval the code directly (using Mozrepl) while I'm coding to see the result.
Is there any way that I can inject/execute a sciprt on Firefox startup, for example ~/.firefox/index.js?
There is no functionality in stock Firefox to execute JavaScript code supplied by the user at startup. Functionality like this has been something that has been requested of Firefox since 2006-04-02.
It is trivial to write an add-on in any of the different Firefox add-on types (XUL/Overlay, Restartless/Bootstrap, Add-on SDK, or WebExtensions) which would run whatever JavaScript you desire upon Firefox startup. This could be done to either run code that was included in the add-on (simple), or that runs the JavaScript contained in a file that is loaded from a location external to the add-on (more complex). Which add-on type you used to implemented this would impact which interfaces you had available within the code you write. One drawback of writing your own extension which runs code included in the add-on is that in order to use it with a release, or beta version of Firefox is that you would need to have it signed by Mozilla. While this is a quick and easy process, it does add some additional overhead to the development/test cycle.
You have not specified any of the firefox-addon tags in your question. In addition, you have not described the functionality you desire, except as generalities. It also does not appear to be the intent of your question to ask how you would implement such an add-on. Given those and the fact that there are already multiple add-ons that implement the functionality of running arbitrary JavaScript (including XUL) code supplied by the user, I am not going to supply code here which performs this function.
However, if you are interested in using an already existing add-on, here are a few options:
userChromeJS: This extension was derived from the code originally provided as an example of how to implement the functionality requested in bug 332529. Its first feature listed is: "Complete chrome customization is possible by running custom javascript code or overlaying chrome with .xul overlays." This is an Overlay based add-on with which you can use XUL. This sounds like the functionality what you are interested in obtaining.
uc: "A userChromeJS clone with built-in subscript/overlay loader capability."
Greasemonkey: "Customize the way a web page displays or behaves, by using small bits of JavaScript." This is a commonly used add-on which permits writing more complex JavaScript code. The code is executed in a sandbox, not in the scope of an extension. This is done for security reasons.
Custom Style Script (Inject desired CSS or JS): "Add Custom JavaScript Codes or Styles (CSS) to an specific page or all pages."
Related
It appears that PDF has, for lack of a better term the "feature" to contain javascript, but luckily it seems there is a change that only some software implements support for javascript
Since web browsers deal already with the issue to handle tons of untrusted input, and hence do some sort of sandboxing, I rather appreciate to open pdf documents inside the browser sandbox via pdf.js. However I wonder if pdf.js will implement the "javascript contained in pdf file misfeature"?
pdf.js still does not support embedded javascript
There are some other implementations (e.g. https://www.pdftron.com/webviewer/demo/pdf-forms) but most of them have some limitations unless you are looking for simple field/form calculations
Update 2022: Since Summer 2021, pdf.js (and by extension, my library ngx-extended-pdf-viewer) uses Quick.js to run JavaScript in a sandbox. You've already mentioned that the browser runs JavaScript in a sandbox, so this is a sandbox running in a sandbox. The Mozilla team didn't want to give the JavaScript code embedded in the PDF file access to browser resources.
If you're using Firefox as a PDF viewer, you're using a slightly different version of pdf.js. It runs the JavaScript code in the same sandbox that runs Firefox WebExtensions.
Here's an article written by the authors of the JavaScript implementation: https://hacks.mozilla.org/2021/10/implementing-form-filling-and-accessibility-in-the-firefox-pdf-viewer/
I am very new to writing plugins for firefox. I am writing a plugin to intercept a URL protocol (I got it here: http://www.nexgenmedia.net/docs/protocol/) inside the plugin and then call some user loaded Jscript functions to pass data.
My question is, How can i call a user script or a greasemonkey script from within a firefox plugin when the plugin is running.
This is generally a very bad idea to run arbitrary code from an extension. The extension code is executed in privileged mode with access to XPCOM (and thus the whole system).
If you really DO want to execute external JS, the best way is Components.utils.Sandbox I suppose. Other options are nsISubscriptLoader or Components.utils.import.
Also, afaik such extensions won't pass security check at Mozilla Addons and won't be accepted there as a result.
I'm trying to write a Firefox extension that intercepts a certain HTTP request and return static content without the request making it to the actual server (similar to AdBlock).
I've looked up the tutorials and I've got a basic file layout. I've also worked out that I need to use the nsITraceableChannel API and add an observer to do what I want and I have example code for that.
Problem is, where do I actually put this code? And when is my extension actually loaded and executed? Is it running constantly and asynchronously in the background or is it loaded per page view?
The documentation doesn't seem very clear on this. This extension won't need a GUI so I don't need the layouting XUL files (or do I?). I tried writing some XPCOM (I don't think I did it right though) component, registered it in chrome.manifest but it doesn't seem to run.
Can anyone explain exactly how the Firefox extensions work and where should I put my actual JavaScript code to monitor requests? Or have I got the whole idea of what an extension is wrong? Is there a difference between add-ons, extensions and plugins?
Concerning the difference between add-ons, extensions and plugins you should look at this answer. But in general, you seem to have the correct idea.
The problem is, there are currently three very different types of extensions:
Classic extensions (not restartless): these will typically overlay the browser window and run code from this overlay. Since there is one overlay per window, there will be as many code instances as browser windows. However, classic extensions can also register an XPCOM component (via chrome.manifest as of Gecko 2.0). This component will be loaded on first use and stay around for the entire browsing session. You probably want your component to load when the browser starts, for this you should register it in the profile-after-change category and implement nsIObserver.
Restartless extensions, also called bootstrapped extensions: these cannot register overlays which makes working with the browser UI somewhat more complicated. Instead they have a bootstrap.js script that will load when the extension is activated, this context will stay around in background until the browser is shut down or the extension is disabled. You can have XPCOM components in restartless extensions as well but you will have to register them manually (via nsIComponentRegistrar.registerFactory() and nsICategoryManager.addCategoryEntry()). You will also have to take care of unregistering the component if the extension is shut down. This is unnecessary if you merely need to add an observer, nsIObserverService will take any object implementing nsIObserver, not only one that has been registered as an XPCOM component. The big downside is: most MDN examples are about classic extensions and don't explain how you would do things in a restartless extension.
Extensions based on the Add-on SDK: these are based on a framework that produces restartless extensions. The Add-on SDK has its own API which is very different from what you usually do in Firefox extension - but it is simple, and it mostly takes care of shutting down the extension so that you don't have to do it manually. Extensions here consist of a number of modules, with main.js loading automatically and being able to load additional modules as necessary. Once loaded, each module stays around for as long as the extension is active. They run sandboxed but you can still leave the sandbox and access XPCOM directly. However, you would probably use the internal observer-service module instead.
i tried to write a script which can be added as an extension to the browser. The problem with this script is how to access the dom elements of a webpage. i used XMLHttpRequest object for accessing the web page but it has same origin policy issues. I worked on it for nearly 3 weeks finally i used Anyorigin.com code but i am not able to get all the functionality so i thought of using userscript where we can easily access the web page's DOM elements. Is ther any other way to create an extension
While enloz's answers are good, Firefox has an Add-on Builder that you can you use.
Add-ons are built using HTML, CSS and JavaScript. There is a web based version with the following features (quoting from their website):
Edit code in a feature-rich environment
Test your add-ons instantly
Use built-in version control & sharing
You can find the web based version here: https://builder.addons.mozilla.org/
Try this:
Greasemonkey:
Customize the way a web page displays or behaves, by
using small bits of JavaScript.
https://addons.mozilla.org/en-US/firefox/addon/greasemonkey/
Update:
This looks to be a better solution, but I haven't tested it.
http://crossrider.com/
In my search for a Javascript way to programmatically select WebView content, I encountered this Javascript code snippet, which uses a method named setData() in a member named clipboardData in the window object.
But when I tried to find documentation for it in a Javascript reference, clipboardData was nowhere to be found.
Why?
Isn't window.clipboardData not part of Javascript or DOM?
No, it's not part of any standard. Except for IE, most browsers don't allow clipboard access because of security concerns (you don't want arbitrary webpages reading something sensitive information that you put into your clipboard).
I believe only IE lets you access the clipboard. Older versions of other browsers used to, but this has been switched off by default as a security measure. Users can explicitly turn it on via settings/options/preferences, but this is obviously not ideal in most situations.
The workaround is to use a flash object on the page. Since Flash 10 added more security layers, user interaction is also required now with the flash object (e.g. a click rather than say onload event).
I found and implemented the good work from the well written article at the bottom of my answer. He explains the issue in more detail, with links to official statements from Adobe/Mozilla and supplies a usable and a downloadable example, and the source code to the fla. This is handy if you want to reskin/redesign his button.
I have tested successfully on Windows7 using latest (as at 7/7/2011) Chrome/Safari/RockMelt/FF/IE7/IE8/IE9 and MacOSX(SL) Safari/FF.
The only downside is that it uses flash which is mostly fine except for some mobile platforms and a small portion of (ab)normal users. Also I found you need to access over http (a web server), opening and using the demo page via the file system (i.e. double clicking the html file in Explorer) won't work.
Thanks for sharing Rahul, awesome job.
http://www.rahulsingla.com/blog/2010/03/cross-browser-approach-to-copy-content-to-clipboard-with-javascript