Funnel cakes and Partner Builds

Funnel cakes

In addition to being an American delicacy funnel cakes are what we call special builds of Firefox. They can come with extensions preinstalled and/or a custom first-run experience.

“The whole funnelcake system is so marred by history at this point I don’t know if anyone fully understands what it’s supposed to do in all situations” - pmac

Funnelcakes are configured by the Release Engineering team. You can see the configs in the funnelcake git repo

Currently bedrock only supports funnelcakes for “stub installer platforms”. Which means they are windows only. However, funnelcakes can be made for all platforms so bedrock support may expand.

We signal to bedrock that we want a funnelcake when linking to the download page by appending the query variable f with a value equal to the funnelcake number being requested.

Bedrock checks to see if the funnelcake is configured (this is handled in the www-config repo)


Bedrock then converts that into a request to download a file like so:


Mac (You can see the mac one does not pass the funnelcake number along.):

Someone in Release Engineering needs to set up the redirects on their side to take the request from here.

Places things can go wrong

As with many technical things, the biggest potential problems are with people:

  • Does it have executive approval?

  • Did legal sign off?

  • Has it had a security review?

On the technical side:

  • Is the switch enabled?

  • Is the variable being passed?

Partner builds

Bedrock does not have an automated way of handling these, so you’ll have to craft your own download button:

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Bugs that might have useful info:

PRs that might have useful code: