For Firefox MOZ_HEADLESS_WIDTH=999

[guest271314]

MOZ_HEADLESS_WIDTH=999 firefox -headless

console.log(screen.width === 999);

[LouisKlimek]

Hey, you opened and then instantly closed this again?

[guest271314]

You don't have a Discussions area. Just another way to detect Firefox headless, by explicitly setting MOZ_HEADLESS_WIDTH then checking screen.width inside of the script.

I was working on trying to close a headless instance from within the script on Firefox. close() works on Chromium. Not very consistent at all on Firefox, including with dom.allow_scripts_to_close_windows set to true. I wound up doing something else that I found to be more reliable to close the headless instance.

I can file a PR to include this hack in tour code if you want, or incorporate the code into your work yourself.

[LouisKlimek]

Yes would be very nice of you if you open a PR. This is definitely a good addition