How to locally run tests in headless mode via terminal command?

[adudyak]

npx codeceptjs run - normal run
How to run in headless mode?
npm run codeceptjs:headless says "'HEADLESS' is not recognized as an internal or external command"

[kobenguyent]

import { setHeadlessWhen } from '@codeceptjs/configure';
// turn on headless mode when running with HEADLESS=true environment variable
// export HEADLESS=true && npx codeceptjs run
setHeadlessWhen(process.env.HEADLESS);

export const config: CodeceptJS.MainConfig = {
...

then export HEADLESS=true && npx codeceptjs run