Similarly for us, gtag (Google Tag Manager) is the biggest third party offender in terms of blocking execution (taking about half a second) as reported by PageSpeed.
I downloaded the theme to be sure and there’s no reference in code.
We have no Custom Pixels.
We only set it up through the “Google & Youtube” Sales Channel.
Hello Denis. I think you might be misinterpreting my comment. I am not offering any fix or workaround. I am simply confirming the issue with additional context and information.