Skip the "welcome to a calmer internet" intro in headless mode

[fulldecent]

You can now use Claude and VS Code to drive your browser. You can use the Firefox MCP servers with Zen and this is an effective way to do work.

But every time you start a session, when Zen starts it has the whole "welcome to a calmer internet" intro which requires a bunch of clicks to get out of.

I am requesting that all of this be turned off when Zen is launched from the command line in dev tools mode from one of these MCP tools.

[Ivaon]

user_pref("zen.welcome-screen.seen", true);

To skip it

[mr-cheffy]

#12959