Chrome Vimeo Iframe autoplay not working anymore

Annotating the <iframe> with an allow attribute worked for me:

<iframe ... allow="autoplay; fullscreen"></iframe>

It's called "Iframe delegation" and is described here: https://developers.google.com/web/updates/2017/09/autoplay-policy-changes.

You need to add &muted=1 to the iFrame src path and you need to add the attribute allow="autoplay" to the iFrame. Now the Vimeo video starts automatically again in Chrome.