Greasy Fork

Go to the YouTube homepage, click on any video to start watching, and then select "Theater Mode"—the script will not work. At this point, refresh the browser to reload the video, and the script will take effect. Alternatively, instead of opening the video directly from the homepage, open it in a new tab—the script will also work. So, why does the script fail when the video is opened directly from the homepage?

Thanks.

The script should work now.

Yes, it's working perfectly now. Thanks a lot!