Skip to content
Demos for new features in Firefox DevTools
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.


A collection of demos for features in Firefox DevTools

We use these for the posts in the Firefox Nightly blog, twitter announcements in @FirefoxDevTools and generally everywhere we want to talk about these features.


Contributions are more than welcome! There are many features and bugs fixed in DevTools every week and we would totally love your help talking about them.

We are creating issues when things are ready to be demoed here too--have a look and see if there's anything you would like to demo!

Choosing a feature to talk about

We want to talk about:

  • new features or closed bugs in DevTools recently, not in Firefox in general. You can find recently resolved bugs with this Bugzilla search (most Firefox Devtools bugs are tracked in Bugzilla, not GitHub).
  • tips and tricks, like the ones described in this page.

To avoid duplicating work, look in the issues page to see if someone is already working on making a demo for a specific feature.

If no one is working on it, create a new issue with the same format so others can find it, and state that you want to work on it. Name the issue in a recognisable way! For example, if you want to make a demo for a feature tracked in bugzilla, name the issue as bug-number - description of bug, where the bug number is the number in Bugzilla. For example, bug 12345678 - demo feature ABC would correspond to the bug 12345678 in Bugzilla. Or if the issue is for a tip, name it like tip-feature XYZ.

Demoing a feature

We suggest you create a new branch to work on the feature. Name it something like bug-number, as it makes things easy to track. Make it your current git branch. Then make a new directory, named like the feature you want to demonstrate (but with hyphens, like this).

The Bugzilla page for the feature will often contain a lot of information, but that is normally just useful for the developer implementing the feature, code reviewers, QA/integration testers, and so on, and very rarely useful for the end web developer that uses Devtools.

Your challenge here is to find a way to demo the new feature to web developers. Some features can be explained with an image. Other features are best demoed with a short screen capture (videos or GIFs, but videos are better, because they can be paused AND converted to GIF if need be). This depends on each feature, and some people simply prefer to see a written description. To top it all, not all features are easily demoable, specially the ones that do not have user visible changes. If you're unsure, tell us about your ideas when you create the issue, and we can provide feedback.

We have also prepared a document providing general advice for creating demos. Let us know if there's anything you miss, or if there's anything you feel should be there too!

At a minimum, a demo folder will contain:

  • index.html page containing HTML to demonstrate the feature. Possibly additional JavaScript and CSS files, if required. This will be linked from the Nightly blog.
  • explaining what the demo is about, how to use the feature, etc. We will use this for the blog post as well as documentation for the tools in MDN, etc. And it's clear what the demo is when browsing the repository.
  • And any additional images, videos or demonstrative assets. It's possible that there are already images you can use in the assets folder. Feel free to use these instead of adding new images.

In case of doubt, or to get inspired, you can look at existing demos and follow the same style.


Send a pull request and we will review and merge the demo if all is good, or provide extra feedback to help you get better at demoing before we merge it into the repo.

We will aim to use it in every available channel, giving you credit. Thank you!

You can’t perform that action at this time.