Why isn't a Test Pilot icon showing up in my toolbar?
Test Pilot can't be installed in private browsing mode, and if you have it installed already, it is disabled in private browsing mode.
Does Test Pilot work in private browsing mode?
Not right now, but we're thinking about changing that. For background discussion, see this issue: #1504.
Why won't Test Pilot/experiments install?
Make sure your Test Pilot add-on is up-to-date. You might try uninstalling and installing Test Pilot if nothing else works. For more details, see discussion in issue #1474
How can I contribute?
First, you will want to take a look at our CONTRIBUTING.md file.
If you'd like to contribute to an experiment, take a look at the experiment's detail page on Test Pilot for the most up to date link to the experiment's repository.
I used to see an experiment, but now it's missing?
We've recently shipped localization for Test Pilot and decided to restrict experiments from certain locales to ensure a smooth roll out. We didn't uninstall any experiments, but if your default language is German, some experiments may have been hidden from Test Pilot.
Experiments you've previously installed are still accessible through
about:addons and can be uninstalled from there. It's also possible that the experiment you're looking for has already graduated.
You can see graduated experiments by clicking on the
View Past Experiments button on Test Pilot.
Why is Test Pilot telling me that something went wrong?
If you've enabled
privacy.resistFingerprinting, Firefox may be blocking add-on installation, and you will need to update your browser's configuration. To do so, do the following:
- Go to
- Right-click on the list of preferences, and select New > Boolean.
privacy.resistFingerprinting.block_mozAddonManageras the preference name.
falseas the preference value.
Otherwise, please see the instructions below to file a bug.
Where can I file a bug?
Test Pilot bugs can be filed on the Test Pilot GitHub repo. link
You will find a link to report bugs for individual experiments on the experiment's detail page on Test Pilot for the most up to date link.
Why do Test Pilot experiments ask me to allow Google Analytics?
Test Pilot uses GA event tracking to measure certain interactions within experiments. We use this data to better understand how participants are using experiments. Each experiment contains a summary description of what data we collect and a link to the precise schema definitions we send to GA. For example, here is the entire metrics schema for Notes. We do not provide any Test Pilot data for use in Google's products & services.
If you're uncomfortable with submitting data to GA, all of our experiments respect the Do Not Track flag in
What browsers are supported by Test Pilot?
While you can only install Test Pilot on Firefox, the site should render and work correctly in the following Contexts.
|Firefox||Release, Release - 1, Beta, Nightly*||Green|
|Firefox iOS||Current Release||Red||#2642|
|Chrome iOS||Current Release||Green|
|Safari iOS||Current Release||Green|
|Chrome for Android||Current Release||Green|
|Focus iOS||Current Release||Green|
|Focus Android||Current Release||Green|
*Firefox Nightly may have bugs that are beyond our ability to support on any given day.
Why not support ESR 52?
Firefox underwent some pretty radical changes for Firefox 57 that make supporting ESR 52 untenable for Test Pilot. We will revisit ESR support in 2018 when ESR is updated to Firefox 59.