Something I've noticed is that if you embed a YouTube playlist anywhere, if you click on "watch on youtube" it will just take you to the first video in the playlist all by itself without the rest of the playlist. This isn't an issue on this sites end, this is purely an issue on YT's end. But pasting a YouTube link on this website and having it auto-convert to an embedded video or playlist is an issue if you only want to link to the playlist and not embed it.
Same with linking a video you don't want to embed. On my SpaceHey profile, I had a picture of an answering machine that you could click and it would take you to a funny video of a message left on an answering machine. If I try to do that on my FriendRewind profile, it either automatically embeds the video, ruining the joke, or completely breaks the profile code because the code doesn't know whether to show the image or show the video.
Basically, unless the video or playlist in question is specifically added to a post with the "add video" feature, it should just be a plain link to the video/playlist instead of automatically converting the link into an embed.