[agiefrh46]

Have you added the strm folder as a tv source in your library?

Yes. Actually I'm using smart playlists to separate TV Shows and YouTube channels.

Did you select YoutubeLibrary as the player in the addon settings?

Tried it both ways. Should try again setting it to YoutubeLibrary and would be back to you with results.

1. By the way. Wouldn't it be possible to add a third option? A shim, that just sends the URL further to the official YouTube plugin while just marking the strm as watched?

2. And while at it, what's the difference between "Update now" and "Refresh Playlist" in the right click menu over the channels inside YouTube Library? I mean what exactly these do?

3. One more thing I noticed: Although the option "Notify on updating of playlist" is off, I'm getting "updating playlist blah-blah" popups every half an hour.

Update:
Yes, if setting the "Play videos from library" option to "YouTube Library" the videos are marked as expected.
However:
- The only way I've been able to force that setting is by disabling the official YouTube plugin completely.
- As a side problem, I'm missing the subtitles that are available with the official YouTube plugin.

4. So, wouldn't the option in question 1 be the best? Is that possible?