Greasy Fork

I had to fix the isTheatherMode function like this

function isTheaterMode() {
    let scrollbarWidth = window.innerWidth - document.querySelector('ytd-app')?.offsetWidth;
    let playerWidth = document.querySelector('#ytd-player')?.offsetWidth;
    let chatWidth = (!document.querySelector('ytd-live-chat-frame').attributes.collapsed && document.querySelector('ytd-live-chat-frame')?.offsetWidth) || 0;
    let isWidePlayer = scrollbarWidth + playerWidth + chatWidth === window.innerWidth;
    return (isWatchPage() && isWidePlayer);
}

by adding the check if the live chat was not collapsed

please update

How did you collocated the YouTube chat window?
Isn't it a property added by external extension?

by adding the check if the live chat was not collapsed

please update

You were right, I'd updated. Thanks a lot!

<3