It's on new new reddit, the one that looks like this: https://i.imgur.com/fp8iUGj.png If you select text, an "embed" button comes up and if you right click on the selection, it and the highlight just disappear and the generic context menu comes up (not the text one where there is "copy", "select all", etc.).
This UI only shows up for me when logged out but they said it'd roll out eventually: https://www.reddit.com/r/reddit/comments/11zso11/an_improved...