What does it mean when the title of the episode has a strike through for text?

When we click on “Show episodes” when watching a set of videos, some of the titles listed have a strike through for text. What does that mean?

Here is an example: https://www.raywenderlich.com/3648-ios-concurrency-with-gcd-and-operations/lessons/10

Does the stricken through titles mean I have already watched them? If so, it’s not keeping up with which ones I’ve watched very well.

Yes, the strikethrough is supposed to show up when you have watched a video. If I recall, it only shows up if you are a) logged in, and b) have watched the entire video.

If you have any suggestions on what would make this feature better/more useful, please let me know - we’re always looking for ways to improve things.

Ok. I certainly will. Thank you for your reply.