The Sorter hotkey seems to fail when used on a YouTube page, but not elsewhere.
Reproduction:
On a YouTube video’s page, I open the sorter by pressing the hotkey. On most pages, the sorter auto-fills the URL, name, and a few other pieces of metadata. On YouTube, however, the sorter fails to capture anything and—if you save the item from there—it’s just saved as a blank link.
If you open the sorter by clicking the menubar item, however, and tap “Capture content from Safari”, it autofills all the relevant info.